My high school had a Sheriff's deputy assigned to us, it wasn't a dangerous area, in fact it was called the "Country Club on the Hill" by surrounding school districts. He was in full kit all day (Which for our area at the time was little more than his uniform and duty belt, no vest on all the time but he had one handy enough), had his own office, did hallway patrols, etc. Everyone knew him, he was a great guy, daughter was a grade below me, etc., so he was really part of the community.
I think that's an ideal sort of situation for school security, and would be a good place to increase the local budgeting for. It would be a good way to alleviate the worries of a lot of people on both sides of the aisle.