Don, I agree. The 30 mins of exercise, though, has to be achieved without any reduction in what is taught, which means that the children/teachers become more stressed as the curriculum is crammed into less time.
Homework? Yes, pointless at that age.
But free time does not equal play anymore. Play is forbidden as being too dangerous. Can't play soccer at lunchtime. Not enough handball courts for so many boys, they are expected to stand around and chat like the girls do.
I don't think school needs to be compulsory until 7 or 8.
