I learned this as a young child in Catholic school.
The following year they started charging tuition. The tuition went up and up each year, and by 7th. grade was so expensive my parents had to pull us out and send us to public schools.
Catholic schools have continued to close down faster than Sears stores ever since. The Church has only itself to blame for walking away from its commitment to education.
Not the Catholic high schools. Not enough seats.