2. A lot of American universities do care about their students having extracurricular activities, but good grades and test scores are still far more important. Also, the admissions counselors are trained to see through a lot of BS that students have done with the intention of impressing them. If you genuinely start clubs that other people join, or start your own school newspaper that people read, that would go over well, but you’ll be asked for letters of reference, and if you claim to have done something very impressive that’s not mentioned in the letters, that might not work out well for you.