Having a 3-day weekend allows for more, along with other things, much more rest and relaxation. It also allows more a longer chance to catch up on homework that was missed over the school week. Another reason is that there is a less chance of a student being absent for school, because a student can't be absent for a school day that doesn't exist. Therefore there is a less chance of them being counted against. There is also more time to visit family members who live far away, so you don't have to worry as much about seeing them on holidays and breaks.