In our school, it is left up to each individual teacher to avoid burnout themselves. Some people do a better job of it than others; I have some colleagues who seem to lead perpetually stress-free lives who come in at 7:30 and exit promptly at 3:15, whose desks are never cluttered, etc. Then I have some colleagues who seem perpetually burdened (like myself) and who are pretty much the opposite. I'm only 33 so I'm still operating at more or less peak efficiency, and I seem to have more patience than some of my older colleagues. I try to avoid burnout by leaving school-related things at school- if it is work related, I try never to bring it home. Having an hour commute before and after work helps decompress me, especially after those "they are dumb as a stump" days. But again, nothing is done schoolwide, even though in a lot of ways the faculty at my school is more like a large extended family.