Although colleges say they want up to four years of a foreign language, I have heard anecdotally that a student should try to reach the highest level offered at the school (even if it’s past level 4). I think AP bio is a more “serious” class than AP Env Sci in the eyes of top colleges, but Env Sci is an important topic for all young people so that’s a bit of a trade off. I agree with prior comments about AP physics being an even better choice…what’s the prerequisite that you’re missing?