What is your financial situation, and what state do you live in? USC isn’t great on FA, and UCLA is going to be expensive if you are OOS. Have you worked with your parents to run net price calculators on all these schools? If not, you need to do that ASAP. Your best bets are to (1) keep working on getting that ACT score up, and try the SAT as well, and (2) do whatever you can in the EC area related to your proposed major. That is assuming your GPA is out of 4.0, if that is the case then you are in very good shape on that metric.