California Institute of Technology's wording, checked October 26, 2026“Tell us about something you created, tested, repaired, modeled, coded, built, or redesigned. What problem were you trying to solve and what did the process reveal to you?”
How to approach it
- 1Name the problem first, then the thing.
- 2Show at least one failure and fix.
- 3Say what the process revealed to you.
A structure that works
One way to shape this answer. It describes moves, not sentences: the words have to be yours.
- 1The problem you were solving.
- 2What you built and how it failed and improved.
- 3What the process revealed.
Where the 200 words go
| Part | Words |
|---|---|
| The moment or example | about 80 |
| What it shows or changed | about 70 |
| Why it matters, or what you bring | about 50 |
Mistakes to avoid
- A parts list.
The checklist our grader uses for this question
When you check your Caltech answers, this answer is read against these 5 areas. Each comes back Met, Partly or Missing with a quote from your draft as evidence, and together with the 200 words limit they set its readiness verdict.
| Area | What a reader looks for |
|---|---|
| Answers the question | The opening sentences answer what was asked, plainly, before background or a hook; every part of a multi-part question is answered. |
| One activity, your role | It is about one activity, job or responsibility, and the applicant's own role in it is clear. |
| A detail beyond the list | It gives a concrete moment or detail the 150-character activities list cannot hold. |
| Why it matters | It shows what the activity means to the applicant and the difference it makes to them or others. |
| Caltech's ask | Names what was made and the problem, and what the process revealed. |
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Questions
More on Caltech and this kind of question
- Tufts: An engineering or science project · 100-200 words
- UT Austin: The activity you are most proud of · 300 words