What shocked me was the discourteousness and ignorance of the professor. A high-profile professor had to lock the door, by such a fascistic method, to resist truancy.
In most states, truancy laws make an exception for homeschooling, meaning that if the parent says they are schooling their child at home they're not considered truant.
Most states have truancy laws that are created to keep students in school, at least up to the age of compulsory education – up until 16, for example, or 18.
Since the dropout problem doesn't start in senior high school, special programs in junior high school focus on students who show promise but have a record of truancy, that is, staying away from school without permission.
Many truancy laws hold the parents accountable for their students' truancy, meaning that even though it's the student who is deciding not to go to school, sometimes the parents themselves are punished for it.