Usually 15-20 minutes before students are allowed into the cafeteria. That gives me enough time to put my lunch in the fridge in the teachers' lounge and boot up my computer so I'm ready for my first hour class (30 minutes later). Then, a coworker and I head down to the restrooms as the kids come into the cafeteria for breakfast. It's one of the places that needs extra eyes. It also tends to head off anybody trying to vape or you know, pierce someone else's belly button. (Yes, that did happen.)