Does being younger than my peers affect or improve my chances of getting into college?

Answered

In most cases, if you are 15 when you apply to colleges you will not be penalized for your age. However, when you apply to top colleges like elites or Ivys your age puts you a great disadvantage over the applicants for a number of valid reasons. The best analogy I can use is the Olympics. You might be a great athlete for a 15 year old compared to your peers but can you compete on the global stage with more mature athletes that have trained harder, have better stats and depth and breadth of their unique talents? It's super rare that you find 15 year olds getting into such schools because the applicants they are competing with have more schooling, harder course rigor, more ECs, more intellectual vitality, honors, awards and chronological maturity.

Some admits at these schools have 4 years of maths (some of them have 6-7 years of math because that have taken differential equations, real analysis, multivariable calculus as well), 4 years of English (some have taken 6,7 or 10 English courses at the college level, I have accrued 11 English courses before I matriculate into Columbia), 4 years of a foreign language (some have studied 2 languages for 4 to 5 years), 4 years of science and 4 years of history. Plus they have either completed the full IB diploma or take 8-12 APs (I have heard of applicants taking 15-17 APs). In addition they have done impressive things outside of the classrooms like serving on various Community Boards, or Board of Directorships, done supervised research, published scientific articles, or worked multiple internships. For sports, many have played a varsity sport for 4 years, some 2 or 3 varsity sports. Some have a level 10 RCM piano certificate or equivalent in their musical instrument. My point is that even if you have a super impressive C.V. Resume, someone 3 or 4 years older may have a more robust and impressive list of achievements.

Getting into a top US college is not a meritocratic process nor is anyone looking at your IQ to determine if you are smartest 15 years old in the application pool. What they are doing is admitting students to shape the kind of freshman class they want to build based on all the various criteria they need to keep the circus going. They need X amount of water polo players, Y amount of cheerleaders, Z amount of legacies (doesn't apply to MIT), W amount of development candidates, K amount of hooked applicants (BIPOC, Low income, First Gen, Non-Binary), F amount of chamber orchestra players, T amount of dancers, H amount of children of faculty and so on and so on. And what you major in matter as well. It's not as rigid as Oxford or Cambridge where you have to pick your entire 3 year course work like "Classics" or "International Law" before you apply and interview for a spot, but it's very similar. MIT doesn't want to admit 1000 CS majors into their Freshman class.

The other factor is your chronological maturity. For many college begins when you are already chronologically an adult at 18 or 19 and you finish up 4 years later. So pre-adulting like living in dorms, frats or sororities, eating meals in dorms or going out to restaurants, bars and night clubs, dressing up for soirees or parties or charity events is something much easier if you are older. It's easier to participate in the college dating scene or hook up culture, it's easier to adult if you are an adult. Now mind you there is a small population of 15 year old college students but I think it would be socially and emotionally difficult to keep pace with cohort peers that are 3 or 4 years older than you.

You must live in another country because most HS students in the US are 18 when they have completed their college admissions process (some 17 some 19).

I've had to answer a similar inquiry to yours multiple times and my advise is always the same. I recommend that you spend a year or two at an Elite Boarding School to get used to idea of living away from home so it's easier to navigate when you arrive at a fast paced urban college campus. Also, you will be exposed to much more difficult course rigor, small Socratic learning styles similar to how courses are taught at top colleges and you will have an opportunity to curate some community service leadership ECs that you might not have under your belt at age 15. Plus if you are not that great an athlete, a couple years on the fencing team or sailing team will help your chances at some schools.

Good luck whatever you decide.

I found this age distribution at MIT for both undergrad and grad school. As I thought most students are in the 18-24 age group. In a separate article I read that there are between 1-5 (14-16 year) olds.

Under 17 5

Under 18 138 138 0

Age 18-19 2,010 2,003 7

Age 20-21 2,029 1,901 128

Age 22-24 2,257 277 1,980

Age 25-29 3,405 33 3,372

Age 30-34 929 9 920