What twaddle.
Counting the time they put in at home and after school, the teachers I know put in at least 10 hours a day. And many of them go to school during the summers.
I'd wager you'll find that to be the case for most teachers.
The only people I know who drive sports cars and have nanny's, and full health insurance , and pensions and summers off and DON'T have work on the weekends and at night , and have to travel all over the world for days on end, are public school teachers.
Give me a break with the checking the homework at night baloney.