My son is in middle school and we not only have several teachers but also the aides that work with them and the gym, music, art, computer etc. teachers. What I did last year was get a bunch of trays with little croissant sandwiches, cheese and a box of crackers, vegetables and dips and sent in plates, plastic ware, and toothpicks for the cheese. I think I also added in a few bottles of soda and cups. This year I am going to the bagel shop in town and having them make up a tray of mini bagles and different cream cheeses and maybe some muffins. I will also bring in orange juice and milk first thing in the morning when they start getting to school.
And then they give me that look when they bring in their child, like "I got you in trouble!" LOL