Very pretty! I couldn't get past the jump before the "woo, let's go!" in level 3, though, sadly. I tried everything I could think of.
For what it's worth, I also got stuck at that point; I just couldn't seem to jump that far. (Lots of landing on the rectangle.)
On the other hand, it's such a relief to play a platformer that doesn't actively hate the player. Soothing music and color scheme, friendly font, encouragement, adequate checkpoints...love it.