if you go to a public school, just have a good/decent gpa (3.0 or higher) and do average on your act/sat.
if you go to private school, have a 3.2 gpa or higher (i had a 3.

and do very well on your act/sat scores. also, write a hell of an acceptance essay talking about how your motivated and committed, and a good leader and all that great bs.
if you do a little below average on your sat/act take it one more time, don't keep taking it for a higher score. my advice if your taking the sat, take it twice - first time focus only on math, second time focus only on english. my advice for the act, answer all questions you know for sure (don't waste times on the harder questions in between), if you run out of time guess b or c (no reason why on b or c, just tends to be the most chosen answers) since leaving a question blank on the act is actually bad.
apply to 2 community colleges, 2 regular colleges, 1 out of state college and 1 dream college. you should be accepted into at least 4 of those colleges.
berkley, brown, columbia, and uw are all great, but don't apply to all of those...apply to maybe 2 of them, you need to have at least 2 back ups (one you like, one you don't) and have a for sure regular college/university. out of state colleges are always a push unless they're a private college (like columbia and brown, ivy league type colleges)
while grades and extracurricular have a pull on your acceptance, you still need a gpa that is fairly above average(hopefully dual enrollment/honors, ap/ib courses being interested in brown and columbia...) and of course the college tests like the sat/act mean everything...the acceptance essay (and any reference letters) are all more like back ups if they're interested in you and 5 other students, thats why having a great one written basically makes it look like your very interested in the school and gives you a bit more pull.
uhm idk, thats all i remember from when i was in hs looking for skool