how to write a college essay for caltech

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How to Write the Caltech Supplemental Essays 2024-2025

Caltech has six required supplemental essays, and three shorter optional essays, although two of them are questions you should respond to. At such a selective school, any extra opportunity to teach admissions officers more about yourself is generally one you want to take.

Because Caltech is one of the most academically rigorous schools in the country, you want to be sure that your essays capture your intellectual and creative potential. In this post, we’ll break down each prompt so that you can know what you need to do to craft responses that truly shine.

One thing to note up front: four of Caltech’s required prompts ask you to write about something to do with STEM. Given that overlap, take care that each essay shares something genuinely new about you, rather than repeating something you already say in another essay. If you’re worried about coming up with four distinct topics, remember that STEM is a broad field, with lots of nooks and crannies to explore. And, we’re here to guide you in just the right direction!

Caltech Supplemental Essay Prompts

All applicants, required prompts.

Prompt 1: Because of the rigorous courses in the core curriculum , Caltech students don’t declare a major until the end of their first year. However, some students arrive knowing which academic fields and areas already most excite them, or which novel fields and areas they most want to explore.

If you had to choose an area of interest or two today, what would you choose? (There are dropdown menus from which you can choose up to two areas of interest.)

Why did you choose your proposed area of interest if you selected ‘other’, what topics are you interested in pursuing (200 words).

Prompt 2: Regardless of your STEM interest listed above, take this opportunity to nerd out and talk to us about whatever STEM rabbit hole you have found yourself falling into. Be as specific or broad as you would like. (50-150 words)

Prompt 3: Tell us how you initially found your interest and passion for science or any STEM topic and how you have pursued or developed this interest or passion. (100-200 words)

Prompt 4:  Tell us about a STEM-related experience from the last few years and share how and why it inspired your curiosity. (100-200 words)

Prompt 5:  The creativity, inventiveness, and innovation of Caltech’s students, faculty, and researchers have won Nobel Prizes and put rovers on Mars . But Techers also imagine smaller-scale innovations every day, from new ways to design solar cells to how to 3D-print dorm decor to experimenting in the kitchen. How have you been a creator, inventor, or innovator in your own life? (200-250 words)

Prompt 6:  Caltech’s values include respect for a diversity of thoughts and ideas. How have you cultivated this value in your own life? (50-200 words)

All Applicants, Optional Prompts

Prompt 7: If there are aspects of your life or social or personal identity that you feel are not captured elsewhere in this application, please tell us about them below. (150 words)

Prompt 8: When not surveying the stars, peering through microscopes, or running through coding marathons, Caltech students pursue an eclectic array of interests that range from speed-cubing, reading, yoga, playing musical instruments and theater arts, to solving puzzles, hiking, painting, and building or inventing new gadgets. We understand that everyone needs an outlet or two. What is a favorite interest or hobby, and why does it bring you joy? (50-100 words)

Prompt 9: Did you have a hard time narrowing it down to just one interest or hobby? We understand – Caltech students like to stay busy, too. Tell us about another hobby or interest! (150 words)

Because of the rigorous courses in the core curriculum , Caltech students don’t declare a major until the end of their first year. However, some students arrive knowing which academic fields and areas already most excite them, or which novel fields and areas they most want to explore.

After you select your area(s) of interest, you are asked to provide the reasoning behind your choice(s). This is a fairly standard “Why This Major?” prompt . This straightforward prompt is intended to give the admissions committee a sense of what interests you, why it interests you, and why/how you plan on pursuing this interest in college and beyond.

Before we continue, we have to address the elephant in the room—what if you’re undecided?

The bad news is that you’re required to pick at least one area of interest on your application. The good news is that you aren’t contractually bound to the area you choose! In fact, “Every first-year student at Caltech takes the same classes during their first two terms; you won’t even declare your major until the end of your first year.”

Don’t worry if you haven’t figured out exactly what you want to do in college—many students haven’t! Look through the list of areas of interest and pick one that’s closely related to a hobby or pastime of yours so you’ll have something to write about.

If you do have an area of interest or desired major in mind, great! Pick that one for your essay.

Now that you’ve picked a subject, you may find it helpful to ponder the following questions before you begin crafting your response:

1) What are your sincere reasons for wanting to major in your chosen field?

Ideally, you will have picked a field in which you have a deep interest—one that you can talk about at length. You should have meaningful reasons for wanting to pursue your chosen field. If your primary motivation involves money, status, or pressure from your parents, you’re already off to a bad start. An essay that seems disingenuous or too self-serving will detract immensely from your application as a whole, so be sure to choose substantial reasons.

2) What are some specific examples of things you enjoy about this field of study?

When answering this question, aim to be as specific as you can. Anyone can write about liking “information and data sciences” or “biology,” so think of more narrow subtopics like “principal component analysis to reduce dataset dimensionality” or “identifying mitotic mutations in fruit flies.” If you’ve picked a topic you’re already passionate about and familiar with, talking about something specific you enjoy about it shouldn’t be too daunting.

3) How does this major serve your life and/or career goals?

You might not have the most detailed plan for your career and adult life, and that’s totally fine! However, it would be helpful if you had some idea of what you want to do in the future. Think of industries you would be able to work in with a degree in your chosen field. What is your dream job? How can this major contribute to your attainment of that job and success in the field?

4) What’s your favorite experience with this subject in school? What are the best parts of your experience with it outside the classroom?

5) Is there any recurring emotion or state of mind that you experience when exploring this field of study? What do you find appealing about that emotion or state of mind?

You can use your answers to questions 4 and 5 to recall some relevant anecdotes that may contribute to your response.

Once you’ve figured out the answers to the five aforementioned questions, you can begin planning a structure for your response. You may find it helpful to break your essay into two principal parts:

• The experiences that fostered and increased your interest in this field (as well as your emotional and personal connection to your chosen major)
• What you hope to do in the future, both at Caltech and in your career

Now, you should do some research on Caltech’s website to find some unique aspects of your chosen major that you can write about. Check out Caltech’s list of majors , as it has links that will lead you to each major’s respective webpage. Also consult their lists of faculty members and research facilities to see what work Caltech is doing in your area of interest.

For example, consider a hypothetical student who wants to pursue bioengineering with a particular interest in stem cell research. She might begin with an anecdote about how her father was a participant in a clinical trial for stem cell therapy after his spinal cord treatment. Perhaps seeing the potential of stem cell treatment opened up a new world for her, which fostered a deeper interest in biology and bioengineering than she had ever had before.

She might write about her high school experiences with biology classes, her intensive preparation for the AP Biology exam, and the bioengineering publications she now likes to read in her free time. She can then transition into a discussion of what kind of research she would like to be a part of at Caltech. A faculty member she can talk about specifically is Professor Magdalena Zernicka-Goetz, whose lab used stem cells last year to create model mouse embryos “that have beating hearts, as well as the foundations for a brain and all of the other organs in the mouse body.”

No matter how unique, weird, or quirky you think your interests are, there will probably be a major or research group at Caltech that can cultivate them. Don’t be afraid to show how unique you are as an individual—that’s the point of supplemental essays!

Regardless of your STEM interest listed above, take this opportunity to nerd out and talk to us about whatever STEM rabbit hole you have found yourself falling into. Be as specific or broad as you would like. (50-150 words)

As Caltech is a STEM-focused institution, unsurprisingly admissions officers want to know all about your scientific or mathematical passions. While the first prompt is focused on your intended major, here, you get the chance to talk about whatever you want in this realm. If there’s something you love learning about, but might not have had the chance to pursue in a formal context, this prompt is a great place to talk about it!

Of course, you’ll want to make sure that what you choose will help you stand out from the rest of the crowd of applicants, so let’s talk about some ways to make your essay unique. 

• Do you have a STEM-related passion that is unusual or unique? Perhaps the passion itself is very specific, or you are approaching a common topic in a different way than others. 
• Have you had any personal experiences that have led you to a passion you wouldn’t otherwise have? Do aspects of your personality or life inform a passion of yours in a way that’s particular to you as an individual?
• How has your interest in a topic evolved over time? Has a run-of-the-mill interest developed into a passion? Has your interest shaped your life or academic journey in a remarkable way?
• Have you engaged with your passion in an exceptional way? Beyond googling, taking classes, or reading books, have you sought out experiences, pursued knowledge, or done some kind of work to spend more time with this topic?

Hopefully, at least one of these questions will help you think of a passion to write about. After that, it’s all about how you frame your story. 

While your first instinct might be to describe your passion in a factual, straightforward way, remember that with any college essay, your goal is to teach admissions officers about who you are, not the topic itself. So, a more effective approach would be to explain how you developed your passion, how it influences your perspective on the world, and how it fits into your broader life and personality.

Let’s look at an example that illustrates how this strategy might look in action. 

“‘Spooky action at a distance’ – how those words send a thrill up my spine! When I first stumbled upon the concept of quantum entanglement while reading an article about quantum computing, I immediately fell into a rabbit hole. Fascinated, I devoured everything I could find on the topic—from Richard Feynman’s lectures to obscure online forums. 

The idea that two particles can remain connected across vast distances, influencing each other instantaneously, blows my mind. I’ve even started experimenting with quantum simulations on my computer, hoping to someday contribute to advancements in quantum cryptography.”

The first strength of this response is that the student has gone beyond the general topic of “quantum physics,” which lots of Caltech applicants will likely be interested in, and focused in on quantum entanglement in particular. This specificity helps demonstrate what interests and perspectives they have that other students might not.

Even better, we learn that they read up on the subject in their free time, which shows that they are a self-motivated learner who pursues knowledge everywhere they can find it–just the kind of student who’s ready to take advantage of all Caltech has to offer. 

Finally, the cherry on top is that they’re already imagining potential future uses of quantum entanglement, which gives Caltech admissions officers confidence that this student will utilize their school’s resources to make a genuine difference in the world.

Tell us how you initially found your interest and passion for science or any STEM topic and how you have pursued or developed this interest or passion. (100-200 words)

Though this isn’t exactly either archetype, looking at our breakdown of the common “Why this Major” essay, or of the extracurricular activity archetype, might be helpful. Like the “Why this Major” essay, this prompt asks you to consider where your STEM interests came from, and like the extracurricular activity essay, it wants you to reflect on something to which you’ve dedicated significant time and attention. 

You have only 200 words to explain both where your passion began and what you’ve done to pursue it since, so you’ll want to choose your topic, and your words, carefully. Consider the following examples of students who sparked their STEM passion in a unique way.

• A student interested in microbiology might write about how their frequent childhood illnesses led to a fascination with germs and all things microscopic. 
• A digital artist could talk about how their desire to animate their creations led to an appreciation of the artistry behind video games. 
• A student whose interest in chemistry began in the kitchen, where they wanted to understand how temperature and ingredients came together to make a dessert come together or fall apart. 

After selecting your topic, you’ll want to think about how to tell a captivating, unique story that shows how your passion has shaped your growth and development. Though this is a STEM prompt, you don’t want to be too technical or information-heavy – at the end of the day, this essay is about you . Your personal connection to, and genuine interest in, the topic are more important than cramming in every single nitty gritty detail.

Let’s look at two examples of the same essay topic – one that is executed well, and the other, less so. 

“When my little brother was fitted with his first prosthetic arm, I was seven and couldn’t stop staring. The way it moved – stiff, mechanical – seemed worlds apart from the ease of a natural arm. I wondered if he could use it to climb to the top of our bunkbeds – but he discarded it a week later, finding it less useful than the stump it was meant to cover.

As the years passed, the memory nagged at me. Determined to make a difference, I began sketching ideas for a more flexible prosthetic, blending art with engineering. I borrowed books on biomechanics and spent evenings tinkering with 3D-printed models in our garage.

In the past four years, my designs have become so much more sophisticated through consultation with a local rehabilitation center, listening to the stories of amputees and understanding their needs. Each interaction deepens my resolve to create a prosthetic that feels like an extension of the body, not a foreign object. As I learn to code and operate 3D printers, my vision has evolved from sketches to functional prototypes. My brother’s smile when he tries on a new, comfortable limb confirms it every time—I’m on the right path.”

Now consider this example:

“My interest in biomechanical engineering began when I observed the limitations of current prosthetic limbs. The rigid, hinge-based designs often fail to replicate the fluidity of human movement due to insufficient consideration of biomechanical principles. To address this shortcoming, I researched the mechanical properties of various materials and their applications in prosthetics. Using CAD software, I designed 3D models of flexible joints that mimic the natural motion of human limbs.

My focus then shifted to material science, where I explored the use of thermoplastic elastomers for creating more adaptive prosthetics. I conducted tensile strength tests on these materials and analyzed their performance under various stress conditions. Through work with users, I gained insights into customer feedback, which informed further iterations of my designs. The end goal is to develop prosthetics that not only restore basic function but also enhance the quality of life for users through superior engineering.”

The second essay may be more informative about actual methods, but the first is more memorable, because it tells you more about the actual student. 

It does this by starting with a vivid memory, which shows the student’s personal motivation for becoming passionate about prosthetics, and goes on to describe how they became more committed to helping amputees through work at a rehab center. The latter essay demonstrates specific scientific knowledge, but we don’t get to learn much about the student themself, and what they might bring to campus. 

Caltech admissions officers are reading these essays to learn information that they can’t get from your transcript or test scores – what kind of roommate you’ll be, for example, or how you’ll navigate the jungle that is a college dining hall. They already know you’re intelligent, so show them what else you have to offer.

Tell us about a STEM-related experience from the last few years and share how and why it inspired your curiosity. (100-200 words)

This prompt is supposed to gauge your interest in and experiences with STEM, both in school and in your personal life. Writing a successful essay will ideally show the admissions committee a few things:

• You are serious about pursuing STEM in college and beyond.
• You have hands-on experience in STEM.
• You have at least some idea of what to expect from a STEM-based education at Caltech.

First, even though the prompt specifies that you can write about experiences both within and outside the classroom, you might find the tips in our guide to the extracurricular activities essay helpful.

To pick a topic, think about the experiences you’ve had with science fairs, robotics clubs, biology or chemistry classes, etc. Narrow down your experiences to the ones that had the most significant impact on your interest in STEM. If you write about an experience that you didn’t have too much emotional investment in, you might inadvertently express a tepid interest in STEM as a whole.

For example, perhaps you worked alongside a pharmacist during high school. Some people consider pharmacy to be more medical and less STEM-related, but the field of pharmacology is indisputably a branch of biology and chemistry. 

Don’t be afraid to bend some definitions when identifying meaningful STEM experiences you’ve had. Caltech is asking you to write a lot of essays about your interest in STEM, and you don’t want to repeat yourself, so getting creative with how you interpret “STEM-related” could serve you well.

You could even get more creative than the pharmacist example above. For example, maybe in addition to loving math, you’re an avid Seattle Seahawks fan, and you once did a project breaking down game film to determine which play calls optimized a receiver’s separation from their defender.

This kind of out-of-the-box approach can be extremely effective for setting you apart from all the other talented Caltech applicants out there, but it’s also harder to execute well. If you’re feeling iffy, stick to something more conventional–a straightforward essay that teaches admissions officers something about you will help your odds of admission much more than a creative one that doesn’t land.

If you’re having a hard time brainstorming, mull over a few questions:

1) What is your favorite STEM-related activity? If you don’t have a good STEM activity, which of your non-STEM activities can be linked to STEM logically?

2) What about this activity generated your interest in STEM? Why did it make you curious and how did your participation in it increase your interest?

3) What went through your mind as you participated in this activity? Do you use any skills that are connected to STEM work, like computation or analysis?

4) Have you developed or strengthened any specific interests because of this activity? If so, what are they and how have they changed over time? For example, you might have been interested in chemistry in general, but this particular activity focused your attention on metal alloys.

5) Are there any specific STEM-related skills that you have developed as a result of participating in this activity? Think about hard skills like chemical titration, building robots, testing the pH of substances, etc.

Once you’ve decided on your activity, you can begin writing your response. Remember to address each point of the prompt:

• How did the activity activate your curiosity?
• Why did the activity activate your curiosity?
• What about the activity made you want to learn more and explore further?

For example, consider the following response by a hypothetical student:

“During my junior year, I joined the Robotics Club with no prior experience, other than having taken AP CompSci. Our team’s first project involved building and coding a robot that could get to distant water sources, collect water, and purify and store it. We spent several weekends and late nights programming the bot and troubleshooting it.

It had trouble navigating at first, then it failed to recognize the water sources. Finally, we completed the build in a few months, and though it was far from perfect, it did the job. That first drink of purified water from the bot was beyond refreshing.

That project was the one that truly showed me how useful robotics could be to humanity. I imagined building hundreds of robots like the original and sending them to developing countries to increase their access to clean drinking water. I am now drawn to mechanical engineering because it offers limitless opportunities to create devices that can be used to improve the world and people’s quality of life.”

This example is effective because it incorporates an engaging anecdote, addresses each point of the prompt, and offers a plan for the student’s college career and future professional life. After reading this essay, Caltech admissions officers will undoubtedly feel more confident about their fit with this STEM-focused institution.

The creativity, inventiveness, and innovation of Caltech’s students, faculty, and researchers have won Nobel Prizes and put rovers on Mars . But Techers also imagine smaller-scale innovations every day, from new ways to design solar cells to how to 3D-print dorm decor to experimenting in the kitchen. How have you been a creator, inventor, or innovator in your own life? (200-250 words)

This prompt is trying to determine how you think as a problem solver. The admissions committee wants to know the ways in which you have been innovative or have approached problems creatively.

Don’t feel like you have to have developed some revolutionary solution to a global problem. No one is expecting you to have engineered some brilliant scientific apparatus—you haven’t even begun college yet! Just like the prompt’s examples illustrate, you can think on as big or as small a scale as you’d like.

When trying to choose an example of innovation in your own life, it might be useful to think about abstract qualities then work your way to concrete events. Are you ambitious, adaptable, creative, resourceful, open-minded? What are some positive qualities of yours? Once you’ve decided on some attributes, you should be able to relate them to some anecdotes.

Let’s say you’re creative and resourceful. Think of a time when those traits generated something innovative or novel in your life. Maybe you were locked out of your apartment and used a credit card to open the latch. Perhaps this experience inspired you to 3D print a plastic card to use specifically for problems like that.

Your story of innovation can involve anything really, as long as you came up with a creative solution to a problem you were confronted with. Maybe the arm of your glasses broke in the middle of class, so you attached a pen cap to it so the glasses could still be used until you had time to replace them.

You have 250 words, so you may want to think of 2-3 anecdotes to discuss. It might even be helpful to write about something you want to improve but haven’t yet. You can talk about a persistent problem you’ve seen and propose a creative potential solution.

Here’s an example of an anecdote a student might describe:

“I worked at a hardware store during high school to help my parents pay some bills. The store was far from my home, and often took about an hour to get to by public transportation. I’ve always been interested in tinkering with mechanical devices, so I decided to make the most of my job.

I bought parts from the store with portions of my paycheck every couple of weeks, and over the course of several months I built myself a bicycle from scratch. Of course, it wasn’t the most visually appealing or comfortable bike, but it did the job and it did it well. I don’t use it much anymore, but I still own it and feel great pride every time I pass it on my way out the door.”

This is a good anecdote because it presents an issue, describes something about the student’s creative and inquisitive nature, and showcases the innovative solution that the student devised.

You may want to approach this prompt in a similar way. Outline a problem you had to deal with, describe some relevant positive attributes about yourself, then explain how these attributes helped you find an innovative solution to the problem.

Caltech’s values include respect for a diversity of thoughts and ideas. How have you cultivated this value in your own life? (50-200 words) 

With this prompt, Caltech is asking not just about your own beliefs, but about how you actively seek out a variety of opinions, ideas, and perspectives, including ones that might contradict your own. The school wants to create a community where different perspectives are respected and celebrated, so they want to see that you’ve demonstrated these values yourself.

You’ll need to consider how you’ve encountered and engaged with diverse perspectives, whether through your interactions with others, involvement in various activities, or personal experiences that have broadened your worldview. Given the word count of less than 200 words, you should aim to be concise, while still providing genuine insight.

Here are some questions to help you decide what to write about:

• Have you been involved in any group projects or teams where different opinions were shared? How did you contribute to or mediate these discussions?
• Have you participated in activities or clubs that exposed you to different cultures, ideologies, or perspectives? 
• Can you think of a time when you had to challenge your own beliefs or assumptions? How did this experience help you grow?
• Have you read books, taken courses, or attended events that significantly broadened your understanding of diverse viewpoints?
• How do you approach conversations or debates with people who have differing opinions?

‌As you select an anecdote or two to use for this essay, remember that a good response will highlight your personal growth and values, describe specific, memorable, unique moments, and will show active engagement with other ideas, not just passive acceptance. The prompt is asking how you cultivate diversity of thought, which is different than just being exposed to differing beliefs.

You also want to be authentic – relying on clichés like “All beliefs are valid” without concretely connecting that lesson to your own personal experiences won’t do anything to set you apart from other applicants. 

Instead, be willing to get a little vulnerable, and acknowledge that your opposition to online shopping, due to the environmental impact, softened when you spent one summer working on a farm, and learned that the owner was only able to get his prescriptions regularly because of delivery services.

To help spark some ideas from your own life, here’s an actual essay that a student could hypothetically write:

“In my sophomore year, I participated in a student exchange program in Japan. The experience was a whirlwind of new customs, unfamiliar foods, and a language I had only begun to learn. But what struck me most was how different the educational approach was compared to my American high school. In Japan, there was a strong emphasis on group harmony and collective success, a stark contrast to the individualism I was used to.

This difference was particularly evident during a group project on sustainable energy. My initial instinct was to take charge and delegate tasks, but my Japanese peers preferred a consensus-driven approach. I learned to step back, listen more, and value the collective decision-making process. This experience broadened my understanding of collaboration and taught me that there’s no single ‘right’ way to solve a problem. Now, I embrace diverse working styles and actively seek to learn from them, knowing that they can lead to richer, more innovative solutions.”

Prompt 7 (Optional)

If there are aspects of your life or social or personal identity that you feel are not captured elsewhere in this application, please tell us about them below. (150 words).

While we typically encourage students to respond to optional prompts, there’s no need to include additional information here if you feel that your application already captures your identity adequately. In other words, this prompt truly is optional.

If you do have something to say here, note that this is a variation of the common diversity prompt . Also be aware of the 150-word limit, which means your response will have to be succinct.

Brainstorming your topic:

Think about communities that you’re a member of, especially those that have played a role in your development as a person. These communities can be physical environments, like the neighborhood you grew up in, or communities defined by attributes, like your ethnic group or gender identity. Remember, identity encompasses a wealth of attributes.

Aspects of identity include traditional markers of diversity, such as ethnicity/race, country of origin, gender identity, sexual orientation, your first language, and an illness/disability. However, aspects of identity also include your hometown, socioeconomic class, groups you’re part of, and even your interests or hobbies.

A quick note if you intend to write about your racial background: In June 2023, the United States Supreme Court struck down the use of affirmative action in college admissions. The ruling, however, still allows colleges to consider race on an individual basis, which is one reason many schools are now including diversity prompts as one of their supplemental essay prompts. If you feel that your racial background has impacted you significantly, this is the place to discuss that.

Because of the wording of the prompt, you might also choose to write about an aspect of your life that isn’t related to ideas of identity. These can include life-altering events, important social interactions you’ve had, or formative experiences.

After you’ve settled on an aspect of identity or an event you deem important enough to write about, consider some questions to help direct your writing:

1) What is the strongest emotion you feel about your chosen aspect of identity or event?

2) Is there a skill, ability, or talent you have due to this aspect or event?

3) Have you developed or strengthened any personality traits as a result of this background? If so, what are they and how have they changed over time?

You don’t necessarily have to include any or all of this information in your response, but if you’re having trouble putting the importance of your chosen aspect/event into words, these questions might inspire some ideas.

Tips for writing your essay:

Once you’ve chosen a topic and have some idea of how you intend to describe it and its importance, it’s time to write. There are two strong approaches to writing this response:

• The first approach involves doing something totally novel. You might want to pick a completely new aspect of your identity or life event that is fully distinct from one previously mentioned in your application. For example, if you mentioned your gender identity already, you may choose to write about your ethnic background here. This can be a useful approach if certain parts of your identity hold a similar level of importance to you.
• The second approach involves building a previously mentioned attribute/event. Perhaps there is an aspect of your identity that is related to the one you just wrote about, but distinct enough to warrant a new essay. Maybe you talked about being Hispanic somewhere in your application previously, and now want to write about the Spanish language. The language you speak might be an integral part of your identity. It isn’t the same as your ethnic background, even if the two are closely linked, so something like that would be fair game for this prompt.

Mistakes to avoid:

Though this response is really whatever you want it to be, there are some things you’ll want to try not to do. Remember to avoid simply listing aspects of your identity without elaboration, writing too much about something negative, and discussing a topic that’s too clichéd.

This is another chance to showcase who you are. During the admissions process, there aren’t too many of these opportunities, so make the most of them!

Prompt 8 (Optional)

When not surveying the stars, peering through microscopes, or running through coding marathons, caltech students pursue an eclectic array of interests that range from speed-cubing, reading, yoga, playing musical instruments and theater arts, to solving puzzles, hiking, painting, and building or inventing new gadgets. we understand that everyone needs an outlet or two. what is a favorite interest or hobby, and why does it bring you joy (50-100 words).

This prompt is meant to gauge who you are beyond your grades and test scores. It’s an optional prompt, but unlike the previous one, we strongly recommend writing a response. Unlike that kind of “additional information” style question , this prompt is specific enough that Caltech admissions officers are clearly looking for a particular piece of information about you. Especially when you’re applying to a school this selective, you never want your application to feel incomplete.

Essentially, Caltech wants to know what interests you outside of school, and what hobbies you might bring to their campus. Your hobbies don’t necessarily have to be traditional extracurricular activities, but you might still want to look at our guide to writing the extracurricular activities essay for some tips!

Before you begin writing, it’s important that you select a strong topic. Of course, you need to be sincere. Don’t write about a topic you don’t consider a hobby just because you think the admissions committee wants to read about it. An authentic topic will always make for a better essay than an extravagant one. Make a list of your most meaningful hobbies and consider the following questions:

1) Which hobby on your list have you shown the most commitment to? Which has been most influential in your development?

2) What is the strongest emotion you feel about this hobby?

• Why do you feel this emotion?
• Has that emotional response changed over time? If so, how and why?
• What emotions do you feel during the activity?

3) What thoughts and feelings go through your mind while you participate in this hobby/activity?

4) Have you developed or strengthened any personality traits as a result of this hobby? If so, what are they and how have they evolved over time?

5) Have you developed any skills due to this hobby? These can include soft skills such as critical thinking, public speaking, work ethic, and teamwork, or hard skills, which are specific to whatever domain your hobby is a part of.

6) What impact has this hobby had on the rest of your life (other activities, social life, academics, etc.)?

Also make sure that the activity you choose isn’t redundant with what you wrote about for Prompt 3, which is somewhat similar. College applications already only give you so much space to share who you are, so you don’t want to waste any of that space repeating yourself! Also note that your word count is lower here than for Prompt 3, so you may want to choose a hobby that’s slightly less central to your identity, or just easier to explain.

Once you’ve chosen your hobby, think about how you want to structure your essay. You only have 100 words, which is a very small space to work within, so you’re going to have to be concise. The prompt specifically asks why this interest brings you joy, so you’ll definitely want to include a response to that question.

You have some flexibility in the way you respond to this prompt. You might explicitly state what you enjoy about the hobby, or perhaps you’ll talk about some of the activity’s outcomes that have brought you fulfillment.

Consider this response from a hypothetical student:

“My fingers pluck each string deliberately but delicately. My foot taps quietly along, keeping rhythm like a metronome. I am at peace, once again practicing classical guitar like I have every day for the past ten years. That seems long already, but there is still so much to learn.

As each mellifluous note wafts through the air, I am filled with the joy of knowing there is another technique to master, another piece to play, another obstacle to conquer. Playing classical pieces is more than a hobby; it is a challenge, an opportunity to honor something that transcends time.”

This is a strong response for a number of reasons:

• First, it uses very evocative language to great effect, painting a picture of the hobby in question.
• Second, it describes in detail the emotions the hobby evokes and the reason it elicits joy in the student.
• Finally, it showcases the student’s perspective in a way that cannot be misconstrued. This student is clearly intellectually stimulated by this hobby, dedicated to it, and industrious when it comes to practicing—all excellent qualities to bring to Caltech.

You should strive to do the same things in your essay. Use imagery to your advantage, be specific when discussing your emotions, and try to describe your emotional response to the hobby in a way that reveals something about your personality.

You want to craft an effective essay, so you should note a few common mistakes to avoid:

• Don’t pick the wrong activity! Bad activities include: hobbies you’ve already written about somewhere else in your application, impressive-sounding hobbies you don’t actually participate in, and hobbies you haven’t actually put that much time into.
• Don’t just describe the interest without elaborating on its impact on you. You might get caught up in your anecdote when writing, but don’t forget to explain the hobby’s significance.
• Don’t just list your accomplishments within the hobby. You shouldn’t simply provide a list of things that make you look good superficially. You want to show your personal perspective and growth by discussing your emotional response to your chosen hobby and how the hobby impacts your life.

Structurally, take a reflective approach and really analyze your thoughts and feelings about the hobby. Since you only have 100 words to work with, avoid writing more than one anecdote. You need to be concise in your language, but as long as you can provide a good reflection and describe what it is about your hobby that brings you joy, you will be fine.

Prompt 9 (Optional)

Did you have a hard time narrowing it down to just one interest or hobby we understand – caltech students like to stay busy, too. tell us about another hobby or interest (150 words).

This prompt is also optional, but it’s another great chance to describe something else you’re passionate about. If you were stuck on Prompt 3 and 8, struggling to choose between multiple hobbies that are really important to you, you have one more bite at the apple here!

Even if you weren’t torn about your topics for those prompts, you should still respond to this question. The extra brainstorming will be worth it–at highly selective schools like Caltech, applicants are often separated by only the finest of lines, so you never know what could make the difference!

Our guide to writing the extracurricular activities essay could once again be useful to you, for tips on how to use your limited space as efficiently as possible. You actually have more room here than you did for Prompt 8, though, so allocate your activities accordingly, based on how much room you think you’ll need to describe them thoroughly.

Consider the following example response:

“When my parents took me on my first snowshoeing trip, I was less than enthused. My blister-prone feet pinched in protest at just the sight of the clunky plastic contraptions, and the rest of my body recoiled too when they announced we’d be doing a night snowshoe. I had a hard time imagining anything could be worth traipsing through subzero temperatures.

But when we emerged from the treeline, I realized that some things are worth any amount of discomfort. Even though my hair was damp with cold sweat and snowfall, and my heels were definitely chafing against my itchy wool socks, my irritation melted away in the iridescent shimmer of the aurora borealis sparkling on unblemished snow. 

Today, whenever I catch myself starting to grumble on an especially cold trip, I remember those colors. They’ll never appear in a cozy cabin–no, they have to be earned.”

This 146-word response just squeezes under the limit, without feeling rushed or like a shortened version of a different essay. The student defines their hobby, paints a picture of their involvement, and includes their emotional connection to the activity. 

We come away from the essay knowing about not only the student’s love of snowshoeing, but also what lessons that passion has taught them that apply to their life more broadly, which is the key to any successful extracurricular essay.

Where to Get Your Caltech Essay Edited For Free

Do you want feedback on your Caltech essays? After rereading your essays countless times, it can be difficult to evaluate your writing objectively. That’s why we created our free Peer Essay Review tool , where you can get a free review of your essay from another student. You can also improve your own writing skills by reviewing other students’ essays.

Need feedback faster? Get a  free, nearly-instantaneous essay review  from Sage, our AI tutor and advisor. Sage will rate your essay, give you suggestions for improvement, and summarize what admissions officers would take away from your writing. Use these tools to improve your chances of acceptance to your dream school!

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How to Write the Caltech Supplemental Essays 2024–2025

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California Institute of Technology , also known as Caltech, is a renowned university that focuses on providing a rigorous STEM education to its students. Caltech’s living alumni include 17 Nobel Laureates, such as Richard Feynman. Other notable Caltech alumni include Stephen Wolfram, Fei-Fei Li, Adam D’Angelo, and David Brin. If you’re an aspiring Techie, you’ve come to the right place. The Caltech supplemental essays include six required and four optional prompts for prospective applicants to answer. Let’s dive in.

Caltech’s 2024-2025 Prompts

Required caltech supplemental essays, your stem future – stem academic interests: caltech has a rigorous core curriculum and students don’t declare a major until the end of their first year. however, some students arrive knowing which academic fields and areas already most excite them, or which novel fields and areas they most want to explore. if you had to choose an area of interest or two today, what would you choose why did you choose your proposed area of interest if you selected ‘other’, what topics are you interested in pursuing (100-200 words), your stem present – stem curiosity: regardless of your stem interest listed above, take this opportunity to nerd out and talk to us about whatever stem rabbit hole you have found yourself falling into. be as specific or broad as you would like. (50-150 words), your stem past – stem experiences: tell us how you initially found your interest and passion for science or any stem topic, and how you have pursued or developed this interest or passion over time. (100-200 words), your stem past – stem experiences (continued): tell us about a stem-related experience from the last few years and share how and why it inspired your curiosity. (100-200 words), creativity in action question: the creativity, inventiveness, and innovation of caltech’s students, faculty, and researchers have won nobel prizes and put rovers on mars . but techers also imagine smaller-scale innovations every day, from new ways to design solar cells to how to 3d-print dorm decor to experimenting in the kitchen. how have you been a creator, inventor, or innovator in your own life (200-250 words), caltech values question: caltech’s values include respect for a diversity of thoughts and ideas. how have you cultivated this value in your own life (50-200 words), optional caltech supplemental essays, if there are aspects of your life or social or personal identity that you feel are not captured elsewhere in this application, please tell us about them below. (150 words or fewer), when not surveying the stars, peering through microscopes, or running through coding marathons, caltech students pursue an eclectic array of interests that range from speed-cubing, reading, yoga, playing musical instruments and theater arts, to solving puzzles, hiking, painting, and building or inventing new gadgets. we understand that everyone needs an outlet or two. what is a favorite interest or hobby, and why does it bring you joy (200 words or fewer), did you have a hard time narrowing it down to just one interest or hobby we understand – caltech students like to stay busy, too. tell us about another hobby or interest (150 words or fewer), have you had any extenuating circumstances (such as limited course selection or disruptions), that have affected your coursework, but that are not described elsewhere in your application if so, tell us about them here., we’ll review your essay.

Receive edits in as little as 24 hours

General Tips

While Caltech is unusual in offering ten essay prompts for applicants to answer, these essays don’t have to be difficult. Before you begin writing the first essay, read through all the prompts. That way, you can pace yourself. If a topic has multiple facets that could be discussed in different essays, versus getting jammed into one essay, then go for it. What might seem like an excessive number of essays to write is actually just an abundance of opportunities to show Caltech who you are.

Moreover, the optional essay prompts are really just that: optional. In order to be effective and boost your chances of admission, your Caltech supplemental essays need to be thoughtful, organized, proofread, and specific. If you only have the bandwidth to bring your best writing talents to the required prompts, you should feel no pressure to write a few more rushed essays. In addition, not all of the optional prompts will relate to all applicants. In other words, don’t try to write responses to the optional prompts if they don’t speak to you. Instead, consider all of the parts of yourself you’d really like Caltech to know, and do your best to incorporate them into the essays you are required to write.

That said, let’s dive in.

Required Caltech Short Essay Questions

Although you’re not bound to study whatever major or area of interest you describe in this essay, you should answer authentically. Through the Caltech supplemental essays, the admissions team seeks curious, driven individuals who already know they want to pursue STEM. Because of this, you’ll want to let your passion shine through.

In addition, whether you have a particular origin story behind your academic interest(s), or you simply enjoy pursuing the questions behind your interest(s), this essay response will benefit from specific details. For example, you hope to study computer science, explain to the reader what kind of computer science you’re interested in, how you became interested in this subfield, and, if you have space, what you hope to do with this degree. Don’t be afraid to sound nerdy!

If there were any details or interests you couldn’t fit into the answer above, here’s your opportunity to explore them further. Note that the wording of the prompt indicates that you should only discuss one rabbit hole in this essay. Instead of discussing all your interests in one place, focus on one topic you’ve regularly been Googling, reading about, watching YouTube videos on, or otherwise researching. Remember, there are quite a few Caltech essays. Therefore, you should aim for depth instead of breadth in this essay. Any topics you wish you could have addressed here, you’ll likely have the opportunity to address in another essay.

This essay prompt has some overlap with the first prompt, which could also involve the origin story of a STEM interest of yours. That said, this prompt could be about any STEM interest, not just your intended area of study. In addition, you could focus this essay on a more specific interest, topic, or subfield than your area of study. In fact, you could focus on a singular, specific topic that is included within your area of study. You could even get as specific as a single question you’ve sought to answer over the years.

If you’re having trouble coming up with topics for this essay, consider focusing on whatever interest has the best story behind it. Note that the prompt expects a singular topic , not multiple topics. This prompt expects you to provide the past, present, and future of a particular interest. Therefore, if you have been pursuing any particular topic for a while, then that topic might fit well into this essay.

This prompt, which is under the same subheading as the previous prompt (”Your STEM Past – STEM Experiences), opens the door for you to discuss extracurricular activities or coursework. For instance, you could describe a lab project in school that inspired your interest in biology. You could focus on an independent research project you have pursued, a summer camp you have attended, a lecture you have heard, or even a book you have read.

The prompt asks you to discuss an “experience,” so be sure to keep your narrative concrete, not abstract. Your essay should clarify that the topic of your essay involved a real-life experience. Then, you should explore how that experience has impacted you and your interest(s).

This essay is your space to describe a project you’ve undertaken, a way you’ve optimized your daily life, a practical idea you’ve come up, or something along these lines. The more creative, the better. Consider the times when you’ve worked with your hands, solved practical problems for your family or friends, or used your technical skills to create something new and unexpected.

The admissions team set this prompt in order to gauge their applicants’ level of creativity and drive to be industriousness in their daily lives. Creativity is great to demonstrate here, but you can also highlight the ways you’ve served others. Not only will you be a student at Caltech, but you will be a peer, a roommate, a community member, and a friend. Therefore, if you have created, invented, or innovated on behalf of others, then you might want to focus on one of those projects here.

Following on the last prompt, Caltech seeks students who will also be thoughtful community members, peers, and friends. Most likely, Caltech’s community will be more diverse than your hometown, given that your classmates will be from around the world. Therefore, the admissions team looks for students who will thrive in communities of great diversity. This diversity not only encompasses identity but also perspectives and life experiences.

Consider times when you have exercised humility, worked to build community, and/or engaged with people who have very different worldviews from your own. Describe who you were in those moments, and feel free to bring up multiple moments as long as you have room to describe each one with specificity.

Optional Caltech Short Essay Questions

Like all of the optional Caltech supplemental essays, this prompt provides applicants with the opportunity to discuss topics otherwise unmentioned in their applications. For instance, if your Caltech application explores your academic and extracurricular interests and achievements but ignores your cultural identity, you might want to write about that topic in this essay. In other words, if there are parts of who you are and how you present yourself to the world that aren’t addressed elsewhere in your application but feel important to you to mention, here’s your chance.

The word “identity” can be treated expansively here. Your identity can include your gender, ethnicity, immigration status, sexual orientation, Myers-Briggs type, political party, religion, and more. Remember, the admissions team has posed this prompt in order to get to know you better. If you were meeting someone for the first time, what would you hope they understood about you? This essay is the right place to answer that question.

The key word in this prompt is “joy.” While brainstorming for this prompt, think about the ways you spend your time. When are you most joyful? What excites you? What do you look forward to doing in your spare time? Here’s your opportunity to elaborate on a source of joy for you.

A “favorite interest or hobby,” in the context of this prompt, should be something that you do simply because you like to. In other words, this activity should not be solely driven by your desire to pad your resume, earn money, or please your parents. This activity should be self-driven and self-motivated.

In addition, this should be a singular activity (see the next prompt). Because most people can write at lengths about their passions, it is important to keep this essay focused on one topic, with a clear beginning, middle, and end. Before you begin to write, consider structuring your essay around an anecdote. You could also write this essay about how your interest/activity/hobby has changed you as a person, a structure which would give your essay a clear narrative arc. However you choose to organize your thoughts in this essay, pay attention to the narrative structure, make sure every sentence relates back to your overarching topic, and be sure to let your joy shine through.

If you found yourself struggling to decide on which hobby or interest to write about while brainstorming the last essay, consider giving one of the runner-ups a chance to shine in this essay. Note that you should only choose to respond to this prompt if you have already responded to the last prompt.

Like in the previous essay, cohesion is essential to making this essay stand out. Don’t mention all your other interests here; the prompt is clear that you’re only supposed to bring up one more interest in this essay. And, once again, joy is key to making this essay feel authentic. Feel comfortable discussing an interest that is similar to the one you already wrote about, or write about a completely different type of hobby if that feels more right to you. Regardless, focus on an activity you pursue that genuinely makes you happy, and your essay will read just as genuinely

This essay prompt gives an applicant the opportunity to bring up a topic otherwise untouched in their application. If your GPA was affected by factors outside your control, your AP exams disturbed or unexpectedly canceled, or another similar issue, then you don’t have to be burdened by that situation in your college application process. Instead, you can elaborate on your unique circumstances here, in an essay with no official word limit.

Be as specific, humble, and honest as you can be here. Moreover, don’t write more than you need to. Although there’s no official word limit on this essay, the admissions officers at Caltech are busy individuals. As briefly as you can, provide the details of your extenuating circumstances, but don’t provide more information than necessary.

If you need help polishing up your Caltech supplemental essays, check out our College Essay Review service. You can receive detailed feedback from Ivy League consultants in as little as 24 hours.

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