Teachers sign a contract every year for X amount of dollars. They can take that amount over 12 months thereby getting paid when school is closed during the summer, or, they can take it over the 10 months that school is in session having a higher monthly pay but they do not get any money during the summer when school is closed. They do not get paid a years salary for just 8 or 10 months work.
The entire argument about how long a teacher works each year isn’t very relevant to overall argument of teacher worth, IMHO. I know that it gets trotted out during almost every debate and it just peeves any person that teaches.
In order to compare salaries with other fields of employment, you need to take the yearly salary and adjust it by the relative number of hours per year actually worked.
For example, I just looked up our school district board minutes. They're hiring a special-ed teacher with BS and 1 year experience for a little over $42K. Taking into account the actual number of educational days in the year (180 versus 250)means she should be compared to a private-sector employee making $59K, which is VERY good money for somebody just out of school.
And in my kids school district, the teachers are out the door and unavailable at the end of the 6 hour school day, versus minimum 8 hours in the regular world, making her salary compare to somebody making $78K.
My wife's friend is a special ed teacher, and to her base salary gets added quite a bit of $$$ for tutoring on the side after school and in the summer (for which she gets an hourly rate)