As to my reasons, start with Skinner.
“What is a ‘teacher’?”
Men and women who have good English and math skills but lack high-value technical skills might choose to become such teachers.
Teachers might provide their SAT scores and college transcript information to prospective parental customers.
Independent certification authorities might thoroughly test the teachers and issue report cards.
https://www.structural-learning.com/post/skinners-theories
I have no knowledge of dealing with rowdy children.
Dear Parent(s):
It seems that we have not been able to get Johnny on the proper track. The tuition you have paid for Johnny will be partially refunded as per our enrollment agreement.