It's not unique to teaching. Your employer will take from you as much as you will give. Worse, your insane hours and effort eventually become the expected minim

It's not unique to teaching. Your employer will take from you as much as you will give. Worse, your insane hours and effort eventually become the expected minimum. To prevent this, many years ago I started setting the timer to 8 hours and 30 minutes (the latter is to account for lunch). Once the timer beeps, I get up and GTFO. No matter what. This works great.