Just unlocked Playroom on first world.
My god, it's brilliant.
Seriously collect them puzzles pieces.
It's kinda funny how puzzle pieces require you to get slow and observant (you can even ignore the clock and after you get the puzzle you may quit the level right away) but the reward they unlock is basically a high skill "speed-run" track.
Also some very ingenious level design in there that forces you to split the body of water to get more points.