Any advice for an upcoming high school teacher?

I will be doing a year-long advanced residency to finish up my Bachelor's in kinesiology w/ minor in all-level teaching. I plan to eventually return to school so I can get a Master's degree to eventually be a professor at a college or university; is there anything I should be expecting whenever I land a job and begin teaching? I know the general census is that teaching eventually gets old and stressful, but I feel that most jobs are like that when you've been doing them for a long time. What should I prepare myself for?