Answer:
Weight in my belly, Trees on my back, I travel fast in my place, but feet is a feature I lack
My head bobs lazily in the sun. You think I'm cute. For my face is yellow my hair is white and my body is green.
No matter how little or how much you use me, you change me every month.
This is rectangular, hollow and has a lid, and where you’ll find it you might wonder, it is just six feet under. What is it?
I'm white, I'm round, but not always around. Sometimes you see me, sometimes you don't.
You use it between your head and your toes, the more it works the thinner it grows.
Difficult
Animal
Easy
Food
Funny
Kids
Logic
What am I?