[wny]

When my daughter was in 5th grade she came home with a graded math test with a question marked wrong, she was quite upset. The answer was correct and the so-called teacher marked it wrong.

[Aevery_Freeman]

In my later years, I left programming and taught high school math/science.

I would correct any errors that the teachers had made in their tests/worksheets.

I even wrote programs for them on the TI's common in the schools so they could check their answers

Was surprised that some teachers got upset.

Never lacked for work though.