There are essentially four types, and I’m broadly stereotyping here:
- The College Prep kid (~40%). This is the most common, at least in the Class of 2019 - 50% of the class went to a private school. This kid went to a private prep school, especially one of the Eight Schools. They did loads of activities, got fantastic high school GPAs (3.9+) and SAT scores (2200+), good chance they did something impressive for their gap year. These students tend to be wealthier, which is reflected in how they dress. These are your college prep kids.
- The Public School Standout (~40%). For the most part they are from wealthier suburbs of DC-NY-Boston, Chicago or California. A lot of these students went to a public magnet high school like Stuyvesant or TJ. This is the most diverse group, featuring 4.0–2400s as well as people with lower scores, but other creative achievements like winning some international competition, or starting a successful community project.
- The International Student (~12%). An upper-class global citizen, usually of Chinese or Indian origin, though they may live in London, Singapore or Dubai. They usually stick with each other, mingling less with the other three types. Disproportionately majoring in economics, though not exclusively so. Disproportionately wear Canada Goose, though not exclusively so.
- The Athlete (~8%). Self explanatory, their athletic skills were the key to their admission to UChicago - although as a Division III school with not much focus on athletics, you can be sure that even the athletes have relatively high scores. The Athlete socializes with other Athletes, and is very likely to participate in Greek life. Typically from the Midwest, since other schools snatch up athletes from other parts of the US.
Edit: Yes, the percentages are based on real data
Edit2: As of Dec 2018, still seems correct