I feel that this scales largely based on subject mater, experience, and past history teaching a particular course. I know a number of teachers and there are a lot of differences. Expectations vary by district, school, and parents. There have been many top down changes over time, mostly for the worse increasing workload.

When I was in HS, it was not uncommon to have lecture most days and a graded assignment once a week or even less. This is obviously a lot less work for teachers. In the best cases it can be a 7—4 job with summers completely off.