Where are my teachers at?

Alright, I'm currently in college and and I've been feeling a sort of tug to go into the field of education. Im currently a biology major and would like to stay relatively close to that path, being that I am very passionate about science! (Maybe a middle school or highschool science teacher?) Anyway, I want some guidance from the lovely teachers of the world! Teachers: Hardest part of the job? Most rewarding part? Are you happy with your career choice? Thank you!!! Comment with any other advice as well!