A beginning teacher needs a manageable workload, a good mentor, and a community.
I'm a novice teacher, and I think about quitting at least once a month. When I talk with friends about work, I get the impression that the only reason they believe my stories is that they're so horrible that I can't possibly be making them up. Who could make up such stories about what that one kid in 5th period did this week, how late I had to stay to coach soccer practice and then supervise a football game, or what a new law about high-stakes tests means for my job security?
But it's not all bad. I love teaching and learning about science. There are few greater pleasures than watching a student studying cells intensely in class—drawing them, identifying them under a microscope, creating analogies for the organelles' functions—and then seeing that student's well-earned look of pride when he or she makes an A on the test. Even watching a perennial slacker's face show some excitement when I mention that Star Wars lied (because there's no sound in space) can make teaching seem like one of the most fun jobs in the world.