Sure, all teachers learn and improve their practice each school year. That's especially true when a veteran teacher changes courses, grade levels, or school buildings.
But that first year or two brings special challenges.
I *thought* was prepared. I had all kinds of tangible and theoretical tools from my grad program; I'd had a good student teaching experience. But there are a few things that no mentor teacher, master's degree, or orientation told me.
Let me save you the trouble of finding these out the hard way!