A quick glimpse inside my classroom right now and you would see 15 (2 are absent) children playing at their "centers." Some are playing with a marble track. Some are playing trains or puzzles, or are at home living. And some are playing with the same giant cardboard blocks that I played with as a child.
In just a second, the clean-up music will come on and they will clean-up; time to pack-up and go home. But for right now they are all playing sweetly. And it is awesome.