My middle son experienced that BS. He brought home papers "corrected" by his teachers. There was glaring incompetence on the part of those teachers. I reviewed the papers and showed him the actual errors so he could do it right in spite of the teachers. He finished high school with a 4.33 GPA including multiple AP courses where he presented course material the teacher assigned didn't understand and achieved the perfect "5" scores on the AP exams.
Good. My “feel good” story of the day. See what your kids not having a father absent family can do?