Cal Poly SLO and USC Chances for Engineering?

I am wondering about the chances of me getting into Cal Poly, Slo, and maybe USC. I have a 3.99 Unweighted, 4.35 Weighted.

250 community service hours, 4 year California Scholarship Federation member, member of the Key Club, member of Athletes Saving Athletes, and I have 3 years of high school swim, 2 JV and 1 Varsity, along with 2 years of beach volleyball.

I live in California, and have taken over 10 AP and honors classes. I also got a 30 and a 31 on the ACT. How are my chances and what should I have done to get into these schools?