Is 29 a good ACT score?

I'm going into 10th grade and just got my ACT score back and made a 29. I hope to take it again to bring math up since I haven't had all of the math that's on the test. If I want to go to Columbia or Stanford what else could I do to stand out? I have helped around the community because I'm in Honor Society and I'm in a few other clubs but what else can I do to stand out besides raise my ACT score? I plan on taking the SAT sometime during 10th grade after we take the PSAT. Oh, I'm also a member of People to People Student Ambadors and I was selected for Who's Who of America or something like that and I have a 4.0 GPA but I still need ways to stand out! Please Help!!