How to Write the Caltech Essays: The Marvelous Guide to Success

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Located in Pasadena, California, the California Institute of Technology has an acceptance rate of 8% and is a world-renowned science and engineering institute with one of the nation’s lowest student-to-faculty ratios.

Despite its small size, Caltech’s contributions in science and research have led to international recognition, including 38 Nobel Prizes.

  • The school also manages NASA’s Jet Propulsion Laboratory and owns and operates large-scale research facilities and a global network of astronomical observatories.

The self-stated mission of this private university is to “investigate the most challenging, fundamental problems in science and technology in a singularly collegial, interdisciplinary atmosphere, while educating outstanding students to become creative members of society.”

If this mission statement appeals to you, you might be a great fit for Caltech.

  • But earning that acceptance letter isn’t easy: Caltech accepts only about 8% of applicants, building a freshman class of just 230 new students.

Luckily, we’re here to help with one of the most challenging parts of the application: the Caltech essays.

We’ll provide all the info and tips you need to write essays that will help you stand out from the competition.

Let’s get started!

What Are the Caltech Essay Requirements?

Caltech accepts both the Coalition Application and the Common Application, with no preference between the two platforms.

No matter which of these options you choose, you’ll also need to complete the Caltech Questions.

The university explains that these questions help them evaluate “your passion for science, technology, engineering, and math.” They’re looking to find out “what excites you, what you value, and which of Caltech’s resources appeal most to you.”

This supplement consists of four short answer questions:

The short answer questions are:

  • Describe three experiences and/or activities that have helped develop your passion for a possible career in a STEM field. Use the separate spaces provided below, one for each STEM experience and/or activity. (120 words for each activity?)
  • Much like the life of a professional scientist or engineer, the life of a “Techer” relies heavily on collaboration. Knowing this, what do you hope to explore, innovate, or create with your Caltech peers? (Your response should range between 250-400 words.)
  • Caltech students are often known for their sense of humor and creative pranks. What do you like to do for fun? (Your response should range between 250-400 words.)
  • The process of discovery best advances when people from various backgrounds, experiences, and perspectives come together. How do you see yourself contributing to the diversity of Caltech’s community? (Your response should range between 250-400 words.)

What Kind of Student Does Caltech Want?

When applying to an extremely selective school like Caltech, it’s important to consider what type of student admissions officers are trying to find.

The goal here isn’t to lie and tell admissions officers what they want to hear; it’s to showcase the aspects of your personality and background that fit best with Caltech’s criteria.

On the university’s website, Caltech writes of freshman applicants, “All we ask is that you share the typical Caltech student’s unbridled sense of curiosity and extraordinary aptitude for and interest in science, engineering, and technology.”

They further explain that they attempt to answer several crucial questions as they review your application:

  • Are you academically prepared?
  • Have you demonstrated a consistent interest in science, technology, engineering, or math? (Are you ready to push the boundaries of scientific discovery?)
  • How will you impact Caltech’s campus community?

Overall, the university is looking for students who not only excel in the STEM fields but are also passionate and excited about exploring these disciplines.

They want creative, curious students who can help make innovative contributions to society.

Caltech also values students who are collaborative and trustworthy enough to work with other Techers in classrooms and labs.

General Tips for the Caltech Essays

On the school website, Caltech explains that—perhaps surprisingly—the way they evaluate applications is “more of an art than a science.”

The admissions team reads every application and every essay to get a sense of who you are and determine whether you would be a good fit for Caltech, pointing out, “You are more than a GPA and a set of test scores!” The university’s advice is to take your time preparing the short answers and essays.

And taking the information in the previous section into consideration, we’ve come up with an additional list of general tips for responding to the Caltech Questions:

  • Be authentic. Your genuine voice should shine through in these essays. Many students will be focused on trying to impress admissions officers rather than on providing honest answers, so one way to stand out is to simply be yourself!
  • Be specific. Another way to write memorable essays is to provide specific, meaningful details. Don’t give the same general, generic answers that admissions officers will read over and over. The more specific you are, the more you’ll stand out.
  • Be enthusiastic. One of Caltech’s key requirements is passion for science, technology, mathematics, and/or engineering. Show this excitement in your essays, and don’t be afraid to “geek out” a little. You should also demonstrate enthusiasm for learning and discovery.
  • Be reflective. You might think it’s obvious how you’ll contribute at Caltech, but spell it out for admissions officers. Relate your responses to the contributions you’ll make in Caltech’s labs, classrooms, and community. Give specific examples of what you’ll do and how you’ll add value to the university.

Now that you know our general advice, let’s take a look at each of the questions you’ll be asked.

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Three Experiences and Activities

Essay #1: Describe three experiences and/or activities that have helped develop your passion for a possible career in a STEM field. Use the separate spaces provided below, one for each STEM experience and/or activity.

First, note the key word “develop.”

  • You should be writing about hands-on experiences with STEM, rather than passive activities like watching a video or observing an interesting lecture.
  • Think of a time you applied your interest or passion in STEM.
  • Consider projects, activities, research, and service. You have a broad range here, as long as you’re writing about your proactive approach to STEM.

Also keep in mind that you’re limited to only 120 words for each entry, meaning you don’t have much space to explore three experiences or activities in-depth. Your best bet is to write three short paragraphs, one for each of the events you’ve selected.

  • It may be helpful to choose some activities that have been mentioned elsewhere in your application or essays. You won’t need to go too in-depth, which will save you some room.

This is a pretty straightforward question, so don’t pressure yourself to think outside the box or get too creative.

You could begin by brainstorming a list of hands-on experiences and activities you’ve had relating to STEM. Then choose your three favorites to write about.

A friendly heads-up: Don’t outsmart yourself for this question. You have three separate boxes for 120 words each, so get to the point, be concise, and choose practical, hands-on experiences. Don’t risk giving background detail or providing an activity that is passive or difficult to write about. Keep it simple.

The Life of a Techer: Collaboration

Essay #2: Much like the life of a professional scientist or engineer, the life of a “Techer” relies heavily on collaboration. Knowing this, what do you hope to explore, innovate, or create with your Caltech peers? (Your response should range between 250-400 words.)

Essentially, this is the “Why Caltech?” question. You can read our guide on how to write “Why This College” essays.

The best way to accomplish this goal is to do your research.

  • Look into specific programs, extracurricular activities focused on STEM, classes, professors, and so on.
  • If you feel the need to address any research opportunities, be sure to do so in extremely specific terms.
  • What project are you extremely excited about? Which professor would you be working with?
  • Why this project and professor in particular?
  • Last, ask yourself how you can pursue these opportunities with fellow Techers.

Here’s how you should go about attacking this essay:

  1. Start by outlining your academic and career goals, as well as your specific area of interest in STEM.
  2. Then explain exactly how Caltech could help you further your interest and reach your goals.
  3. Discuss team dynamics and how you can leverage other students’ talents and experiences to accomplish your mission.
  4. Make sure you’re discussing opportunities and experiences unique to Caltech, rather than qualities that many other schools share as well.

It’s vital to be extremely enthusiastic in this essay.

Are you excited about Caltech? Excited enough to be one of just 230 students who receive this opportunity? Show it.

For example, here’s a successful outline of a Why Caltech essay:

  1. Your community was hit by a drought last year. It made you think about how communities in developing countries or those without infrastructure can survive such harsh climates.
  2. Your engineering team in high school designed a national irrigation system that adjusts the supply of water over a 300-mile mile radius. This irrigation system utilizes algorithms and radars to make its decisions.
  3. At Caltech, you want to work with research partners to discover how you can not only bring this irrigation system to life but also implement machine learning and AI to increase its deployment accuracy. Describe how you’ll work together.

Remember, never write about location or legacy. Southern California is a beautiful place, yes, but there are other schools in SoCal besides Caltech. Demonstrate that you took the time to research Caltech and how you fit within its community.

What Do You Do for Fun?

Essay #3: Caltech students are often known for their sense of humor and creative pranks. What do you like to do for fun? (Your response should range between 250-400 words.)

Think about your hobbies, possibly putting together another brainstorm list.

  • What do you do in your spare time?
  • List as many activities and interests as you can.
  • Then, review the list for the most “unusual” way in which you have fun.

This doesn’t have to be something tremendously unique, just something unusual that not every teenager engages in.

  • Avoid obviously common hobbies like reading, listening to music, playing video games, watching TV or movies, or playing sports (unless you play cricket, curling, or something else uncommon).
  • Perhaps you collect Russian nesting dolls or build elaborate forts with your friends.
  • Maybe you go on fun scavenger hunts around town or devote every Saturday to browsing yard sales for the best deals.

This isn’t a serious question and doesn’t require a serious or academic answer.

For this prompt, you do have enough room to vividly describe the unusual activity you enjoy.

Tell a story and include sensory details. If possible, you may want to see if there’s a way you can continue pursuing this unique activity at Caltech.

If not, maybe you would want to start a club of your own! Colleges love proactive students.

Irrespective of the hobby you choose, be sure to select one that has had a tangible effect on your life. Choose a hobby or pursuit that has changed you. Then, explain how it’s changed you.

  • Do you train Brazilian jiujitsiu? Has it changed the way you approach competition and solve problems?
  • Did you create an app for your school? What did you learn about solving a community’s problem using iOS or Android?

While it doesn’t need to be STEM-related, it should be substantive.

Contributingg to Diversity at Caltech

Essay #4: The process of discovery best advances when people from various backgrounds, experiences, and perspectives come together. How do you see yourself contributing to the diversity of Caltech’s community? (Your response should range between 250-400 words.

This question makes it clear that diversity comes in many forms. Diversity of experience, background, and thought are specifically mentioned, but you can think of any way that you might bring an interesting or unique perspective to Caltech.

  • For instance, you might choose to write about your approach to solving and analyzing problems or generating ideas.
  • How does your approach differ from others?
  • What problems have you been able to solve, as a result, that others haven’t?
  • And how could this help you contribute at Caltech?

You might also have a unique cultural or economic background, or experiences that you think will allow you to offer a fresh perspective at Caltech. There are many different ways to answer this question.

However you decide to approach the question, try to offer a supporting anecdote (a story that demonstrates the diversity you’ve mentioned) and explain how you’ll put this diverse perspective to use at Caltech.

Brainstorming the Caltech Essays

Here’s a helpful exercise that has helped a number of our students who have gone on to study at Caltech.

Exercise 1

List three to seven books (titles and authors) that have been meaningful to you, each with a one-sentence summary of how that book has influenced you.

These don’t have to be math, science, or even academic texts.

  • If you learned a valuable lesson from a fictional character or bonded with new friends over your love for a YA novel, feel free to include it here.
  • You may want to include one book title that is in some way related to STEM. After all, your passion for science, math, and technology should be the focal point of your application.
  • Lastly, we recommend avoiding any potentially controversial topics. You never know who will be reading your essays, and you don’t want to offend the person who holds your fate in their hands!

This exercise will help you broaden your thoughts and keep you from writing a cookie-cutter essay. Yes, it’s important to demonstrate your academic gravitas, but it’s also critical that you leverage other important aspects of your personality.

The books you’ve chosen for this list can demonstrate how you value knowledge and the interests you’re most likely to pursue once you’re in college.

Even if your interests are likely to change, this list will jog your memory and help you raise interesting points about yourself.

Exercise 2

We mentioned above that Caltech values students who are trustworthy. The school is a close-knit, collaborative community, so honesty and integrity are vital. Here’s your opportunity to demonstrate that you possess these qualities.

  • Come up with an ethical or moral dilemma to discuss.
  • It doesn’t necessarily have to be a major problem, just a time you’ve had to make a challenging decision.
  • Can you think of a time, possibly within your high school community, when you were faced with a tough choice, ultimately deciding to do the right thing?

Then, explain your problem-solving process, or how you arrived at a solution.

  • Briefly introduce the problem and how you felt about the situation.
  • Then, explain the factors you considered and the specific steps you took to arrive at a solution.

You don’t have many words to tell the story here, but try to include a few vivid details that can bring your experience to life. Show action. What did you do to solve the problem or come to a solution?

This is an unorthodox brainstorming exercise, but it will help you think three-dimensionally about your life and ability to create solutions. Creating solutions is, by definition, hands-on work, so this exercise is a good way to think critically about action steps you’ve taken to change your life or someone else’s.

Conclusion: Writing the Caltech Essays

Aspiring scientists and engineers from around the world dream of becoming a Techer. When applying to such a highly selective school, your essays are among your best chances to set yourself apart from the competition.

  • Use the tips we’ve provided here for your four short answer questions. Be passionate, authentic, honest, and specific. Show your aptitude and enthusiasm for STEM, as well as your profound interest in Caltech.
  • Don’t forget to proofread!

You might earn the opportunity to join the brilliant and innovative minds at Caltech next fall!

And if you’re interested in gaining an edge in college admissions essay writing, check out our college essay boot camp.