Complex sentence: They go into the cafeteria late and end up sitting in the LBR section but unfortunetely the school has decided anyone isitting in that group will have to be moved into trailers and go to school there.
Split into simpler sentences: They go into the cafeteria late and end up sitting in the LBR section. Unfortunately, the school has decided anyone that is sitting in that group will have to be moved into trailers and go to school there.