How to stand out to colleges

Pre-College Issues Summer Programs
1

Hi everyone!
I have a few questions about how I could stand out to colleges over the summer or when I have time. I specifically want to get into a college related with science or engineering (really hoping to get into University of Chicago and MIT).
So here are the questions:

  1. What programs can I take/do over the summer or during the school year to show my math abilities? I like math but I am not the best at competitions. While this is the case I still believe I have an aptitude for math.
  2. What science programs can I do?
  3. What really makes me stand out in a college that I’m looking for?

Any answers would be very useful and thanks to anyone who decides to reply.