Thighs!!! Help, please! :)?

So, lately I've been working out, & about a week ago I did about 130 reps on a seated leg press, rode a stationery bike for 15 min., & did that little stride thingy (my legs were SORE! lol) & I've noticed, to my satisfaction, that my thighs look slimmer & they're feeling harder & more muscular around my quads & hamstrings & stuff. But my thighs are only smaller up until my upper thigh area (my adductors & abductors, I think they're called). That's the worst part of them, pretty much, & I want to know some sure-fire ways to make my upper thighs slimmer, too. It's really bugging me! I'm 15, by the way. Thanks! :)