This happens all the time, but is never followed up in public schools. And on those rare occasions that complaints are taken seriously, the teacher in question is simply suspended with pay or transferred to work at the Bd. of Ed.
This used to happen all the time in NYC, and 110 Livingstone Street (until recently, the headquarters of the system) seems to have been populated mainly by child molesters and a few crooks who had dipped into their school's petty cash fund, since the union made it impossible to fire them.
Statistically, btw, public school teachers are way over the Catholic clergy. But the press loves public schools and hates the Catholic Church, so guess which gets the most coverage.
Fear for your children.