The Common Application is a portal that allows the applicant to apply to multiple universities at the same time. The Common App currently serves over 750 universities.
The 2018-19 Common App asks you to choose one out of seven prompts, for an essay ranging between 250-650 words. The most popular question last year was "Discuss an accomplishment, event, or realization that sparked a period of personal growth and a new understanding of yourself or others."
In addition to the common essay, universities ask specific supplemental questions in order to better evaluate the applicant's fit with the particular institution. The supplemental questions usually seek to probe why the student wants to attend that particular university, why the student chose that particular major, and why the student would be a good match for that particular university. Please see below some of Stanford's supplemental questions, for an example.
Supplemental essay Questions from stanford
"Candidates respond to all three essay topics. There is a 100-word minimum and a 250-word maximum for each essay.
The Stanford community is deeply curious and driven to learn in and out of the classroom. Reflect on an idea or experience that makes you genuinely excited about learning.
Virtually all of Stanford's undergraduates live on campus. Write a note to your future roommate that reveals something about you or that will help your roommate—and us—know you better.
Tell us about something that is meaningful to you, and why?"
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