What is an A day / B day or “Flip” day schedule?

Core teachers meet to make up their team schedule for the week. An “A” day means that students should attend their classes in chronological order (periods 1-9). A “B” day, however, simply means that the core classes are reversed, and they the students will have their regularly scheduled morning core classes in the afternoon, and their regularly scheduled afternoon core classes in the morning.  Lunch periods, foreign language classes, PE and electives are not affected by the “A” day “B” day flip. These schedules are updated weekly and posted in various places in the school building.