“OK kids, you can stop your creative paper folding exercise now and the monitor will collect your products for evaluation. And now, let’s take a break from all that with a quick game of Drill’nKill!”
Many traditional children’s games have a high level of rote learning and/or rule-based behaviour.
Most scientists consider their nominal work to be a form of play.
It’s all in the attitude (which is hard to define and quantify), and I suspect that a lot of educational “research” is confounded by subtle infections of attitude which dominate whatever effect is purportedly being observed.