How to Write the CalTech Supplemental Essays

This prompt invites you to share the reason behind your interest in an academic field. Your response doesn’t need to be particularly groundbreaking, but it should be truly authentic. Is there a project from high school that developed your interest in this subject? A book that ignited your curiosity in this area? A summer program that introduced you to this field of study? Draw on some unique experience to show rather than tell your reader how you arrived at this interest. A word to highlight in this prompt is “excite.” Don’t hold back on expressing your intellectual curiosity and enthusiasm!

I want to be a fortune teller.

No, I don’t need a crystal ball; my computer will suffice. My fascination with forecasting impending events has made me fall in love with economics and quantitative analysis.

In high school, I worked with my economics teacher to develop an independent study in econometrics, where I attempt to predict the unpredictable. While my project is specifically about discovering the determinants of success in the Major League Baseball playoffs, what it really seeks to understand is how to better measure labor performance—in this case, that of professional athletes—which may be overlooked. Sports, specifically baseball, are a terrific sampling ground for labor analysis and prejudice regarding labor. In baseball, scouts historically value simplistic factors like players’ win-loss records or 40-yard dash times; however, the “Moneyball revolution” helped teams to discover that there are players who struggle in traditional aspects of evaluation but possess undetected, often incredible, traits with their own inherent value. At Caltech, through courses like “Introduction to Econometrics and Applied Mathematics,” I hope to develop the analytical capabilities and data-driven approaches that would allow me to eschew orthodoxy in favor of identifying the “diamonds in the rough.”

Just like in the previous prompt, Caltech wants to know what excites and stimulates you intellectually. Because of how similar this prompt is to the first one, make sure to use this space to reveal something new or to show a different side of you to the admissions committee. Is there a niche topic you’re obsessed with? Is there a problem or question you have spent days wondering about? What subject could you talk about for hours? This prompt is intentionally broad and gives the opportunity for eccentricities and personalities to shine! Once again, do not hold back on enthusiasm. Caltech should read your response and be able to tell how passionately you care about a certain topic, subject, or other intellectual pursuit. A successful essay would likely also demonstrate how you’ve interacted with this interest in your own life and how you might continue to do so on campus at Caltech.

Upon waking, I immediately roll over and grab my pen and notepad from my nightstand and begin scribbling, my eyes barely open. Ever since I was little, I have been obsessed with decoding dreams and uncovering the messages behind their vivid imagery. Learning about lucid dreaming and REM sleep fuels my curiosity about the mind, and stacks of “Dream Dictionaries” frequently litter my nightstand.

As I’ve grown up, this obsession has flowed into other areas of neurobiology and psychology, from memory retention to goal-setting. I initiated “Thriving Tools” at my high school, an educational series aimed at empowering fellow students with science-backed strategies for improving memory, motivation, and effective learning. Friends’ successes—better sleep, information retention, and increased classroom confidence—were the ultimate reward.

At Caltech, I hope to further my scientific understanding of biology and to then utilize this information to create a community where people feel healthier and more empowered.

Note that this prompt is two-pronged—it first asks you to describe what inspired your STEM-related interests, then they ways you have actively pursued those interests. The first half allows you to narrativize your beginnings in the STEM field, and as such, consider beginning with an engaging story to illustrate your burgeoning interest. The next thing that admissions officers want to see is a demonstration of initiative. Admissions officers want to not only read about how you first dipped your toe in this topic or passion, but how you then went above and beyond in pursuing this passion. How did you explore it beyond the classroom? How has this passion grown and what has it culminated in? The more specific you can be in your writing, the better. Finally, how will you continue to develop this passion and show initiative on Caltech’s campus?

Crouching in the corner of my mom’s office, I lifted the lid of the Tupperware container, eager to see what awaited. A gigantic smile spread across my face as I saw the treasure beneath: oozing strawberries covered with a fuzzy layer of white mold!

While this may sound like many people’s worst nightmare—my mother included—this moment was pivotal in my development as a scientist. I was in fifth grade when I became troubled by how strawberries in our fridge grew moldy in a matter of days. Determined to find the storage method that ensured the longest freshness, I placed strawberries in four different types of containers and tracked the mold growth.

Seven years later, not much has changed—just replace the Tupperware with Petri dishes and the moldy strawberries with incubated bacterial colonies. My internship with a local clinical laboratory has only deepened my passion for microbiology. Hands-on experiences like plating Petri dishes, culturing bacterial strains, and counting colonies probe me to ask even more questions. I am proud that my fifth grade strawberry experiment was just the first of many, and I hope to take advantage of Caltech’s extensive research opportunities to continue exploring my beloved biology.

This prompt is fairly straightforward in that it requires you to share some sort of anecdote related to a STEM experience. Make sure you are not just telling the story, but showing it through visual language and storytelling. The important thing to keep in mind is 1) to connect this to yourself and how this experience nurtured you as a curious intellectual and 2) to express how this experience aligns with Caltech or an opportunity you hope to pursue at Caltech.

Intergenerational friendships are some of the most rewarding relationships. I should know; some of my dearest friends are over a thousand years old.

Last summer, I conducted environmental research focused on forest management across California redwood forests. Through this experience, I was able to bear witness to the great beauty that lies in these ancient, towering trees. Beyond their beauty, though, I was taken aback by how much there was to learn from them. My curiosity was sparked throughout my time as a researcher as I learned more about redwoods, from their remarkably high bark moisture content that makes them fire-resistant to their incredible carbon sequestration abilities. This experience taught me that, in a society where humans are often prioritized over other living things, it is essential to raise awareness for the well-being of plants and animals, including the underlying wisdom they provide. Through Caltech’s Environmental Science and Engineering program, specifically exciting classes like “Forest Ecology” and “Climate Science,” I hope to continue pursuing this curiosity about the natural world and to equip myself with the skills necessary to create solutions to environmental challenges that keep the needs of both humans and plants in mind.

This question is prompting you to highlight a time when you have thought out of the box or brought a unique idea to completion. Given that creativity is the focus of this prompt, consider how you might incorporate other disciplines into your answer, get creative with your storytelling, or select an off-the-wall anecdote to highlight your innovation. The idea of being a creator or inventor also implies a sense of initiative, grit, and leadership, so think about how you can showcase those qualities with your answer. Finally, end the essay by connecting this anecdote with how it informs the type of student or person you will be at Caltech and the impact you hope to make on the community there.

“We’ve got a breach!” the special forces leader shouts, turning on the alarm and triggering signals throughout the museum. Flashing red lights illuminate the scene. Despite the villain’s success in sneaking over the fence, his plan is ultimately foiled.

While many would recognize this as a gripping action scene, few might connect it with the body’s immune response. Yet, during an AP Biology lecture on infection, I noticed striking parallels between our reactions to pathogens and the riveting scenes of my favorite movies. The vivid imagery of pathogens as villains and components of our immune system as various layers of defenses took my understanding of these processes to a new level.

Inspired, I combined my passions for biology and writing to create a play that translated scientific concepts into compelling narratives. After presenting it in class, I noticed that my framing of the immune response as a story helped my classmates not only engage with the material on a deeper level, but also retain information more effectively.

Encouraged by this feedback, I took my play to middle schools, hoping to bridge science and arts at an earlier age. I volunteered weekly to rehearse scenes and discuss their connections to immunology. Experiencing students’ overwhelming enthusiasm proved to me the value of combining two seemingly-opposed areas like science and art.

Caltech’s focus on interdisciplinary approaches aligns perfectly with who I am as a student and creator. At Caltech, I will continue integrating my passions and inspiring others to see the interconnectedness of disparate fields.

At college, there will be people from all walks of life and from many differing perspectives. This prompt is all about demonstrating to Caltech that you are open to perspectives other than your own and that you don’t just speak, but you also listen. Is there a time you have had a difficult or uncomfortable conversation with someone who held a different belief than you? Is there a time you helped facilitate a discussion amongst people of opposing views? Can you think of an experience when you found common ground with someone incredibly dissimilar from you? This prompt, of course, should include a specific anecdote or experience.

“I don’t know if I agree with that interpretation.”

Those nine words introduced the majority of my contributions to discussions in AP American Literature. When the semester began, I worried that those words would cue a collective eye roll from my peers—that fellow students would see me only as a contrarian. However, I couldn’t resist the near-scientific impulse to investigate ideas from different angles. I have always been the “loud-mouth” in my family, and while I know it is a gift, my outspoken nature often used to feel like a curse.

Despite my initial fears, my class grew to become close friends. I soon found myself on the receiving end of those nine words, as classmates became emboldened to test their own ideas and question those of others.

The class quickly became my favorite; I learned to disagree well, examine my own preconceptions, and expand my perspectives to others’ views. My classmates helped me see that my willingness to question ideas—and openness to having my own perspectives and opinions tested—helped to foster the atmosphere of curiosity and trust that we all came to appreciate. It is this inquisitive yet open nature that I hope to bring to Caltech’s classrooms.

Almost all of the prompts thus far have been directly related to your interest in STEM, so you should use this space as an opportunity to show off a side of yourself or a part of your identity that you haven’t been able to yet! This could be a community that has shaped you, a hobby not yet talked about, or a culture you are a part of. The prompt is very open, so it would be a good idea to use a short anecdote (remember, maximum 150 words!) to structure the flow of your essay. Make sure to connect this anecdote to how it has impacted you as a person (i.e. how you see the world, how you treat others, how you approach challenges, etc.).

This prompt is the perfect place to be playful—no hobby is too big or too small! This is an opportunity to step away from writing about pure academics, and it is a great way to humanize yourself and show Caltech the nuances that make up who you are. Write about something that you haven’t talked about yet in your application, and express why this interest or hobby is so meaningful to you.

Since this prompt is so similar to the last one, be sure to choose an activity, interest, or hobby that is completely different from what you last wrote about. This is an opportunity to add further dimension to your profile, so show a side of yourself the admissions officers haven’t yet seen!

This is your chance to explain any difficulties or gaps in your application. Does your school only offer 2 AP classes and that’s why you didn’t have more on your transcript? Did you go through a hardship during high school that took away your focus or time from schoolwork? Did you have a younger sibling you were responsible for taking care of after school, which limited your ability to pursue certain opportunities? A good tip is to highlight instances where you were able to recover despite these challenges or show growth after these hardships.