Treehouse - I managed to climb my way to this area of the treehouse and couldn't find another way out except for...

A Slide - Yet another slide, this one a spiral.

A Whale! - Of course, you can walk into the whale's mouth. In addition to all the treehouse stuff, there's a huge "Enchanted Caves" area back behind the whale. Under this floor is a tiny "underground whaleway" passage too small for me.