My girls went to a public elementary school - and they did have one recess. However, for their middle school years, we were able to send them to a small, private Christian school. There, they had two recesses - morning and afternoon - because the administration realized the wisdom for these kids to get out and run around a bit. :)
You are exactly right about getting out and blowing off steam. Kids need a break to be kids and burn off that huge surplus of energy they have. Sitting in a chair for hour after hour is not only boring, but it is not healthy for youngsters. Why is this such a huge concept our “educators” can’t understand? When the kids get into middle or junior high and high school they need some kind of organized exercise. It is even more important at grade school level where the kids are bubbling over with energy that needs burning off. This is not rocket science.