Food is subsidized, so let's say about $100/month/kid is going to help pay for their school lunch. There's $36,000 a year gone.

Arts classes requires materials. Instruments for band. Mopping the classrooms. Maintenance for desks.

Some of those kids go to detention, so now some teachers get paid overtime to sit with them.

The football team takes the bus to go somewhere.

The library buys some new books. Updates the computers.

There's a lot of stuff going on, it's not just the teacher.