Well, according to a quick "google", there are approx 1500 middle schools & 1500 high schools in TX.
So reasonably assuming if 75% of them have this fee (a whole lot do from what I've seen on the net) that makes about 2250 schools - so let's round it down to 2000 to be conservative.
Now...
It's not entrapment & it's probably legal, might depend on your State.
Consider this - it's still a developing legal area, but current state of law in most states allows Law Enforcement to put a concealed GPS tracking device on your car without your knowledge & in some states without a...
A Texas Education Statute authorizes school boards, at the board's option, to establish policies for the seizure of cell-phones from students who use or display them in violation of school policy. (Most schools allow possession, but they must stay turned off & not used or displayed till school...