Some Washington, D.C., charter schools expel or suspend large numbers of students.
This teaches them a lesson. If they misbehave, if they break school rules, they are out, perhaps permanently.
If they are expelled, they go back to the public schools.
If they have low test scores and they are expelled, the charter school gets higher test scores, and the public school gets lower scores. If they are troublemakers, the public school gets the troublemakers. The charter school keeps the students who obey and get good test scores.
This is what George Lakoff of Berkeley describes as the “strict father” philosophy now so popular among conservatives. There are rules, the rules are always right. Obey or be banished.