In my case, I had mostly A’s (though not all – but my B’s were in AP classes), I was in drumline in the marching band for a few years, I was president of the French Club, a member of the National Honor Society, and on student council, among other things. I volunteered as a tutor and at a preschool throughout high school as well. I don’t have rich relatives but they didn’t seem to hold that against me 😉

But everyone is different. My best advice would be to play the sports that you like, join the clubs you’re interested in, volunteer if you have time, take tough classes and keep your grades up, write a good personal statement, and develop relationships with teachers so they can write you good letters of rec. If you don’t get into Stanford, you’ll get into somewhere else just as good 🙂

Good luck!