Parasitoids of flies
Fly parasitoid wasps are nature’s own enemy of all common manure and rotting organic matter breeding pest flies, including the common house fly, horn fly, biting stable fly and lesser house fly. Fly parasitoids hunt out and attack fly pupae (cocoons) before the flies emerge and reproduce. They are tiny, completely biteless and stingless. They never become a pest themselves or bother people or animals.
Teachers can call 888-562-5696 and order a shipment of 5,000 “Fly Predators” from the company called “Spalding Fly Predators” to be shipped to their classroom for $19.95 + tax. The current mixture of parasitoid species marketed under the trade name “Fly Predators” include: Muscidifurax raptorellus, Spalangia cameroni or Spalangia endius, and Muscidifurax zaraptor. Teachers could ask students to research these species before the shipment arrives. Link to video on how to release the wasps (external retail site)