Ruff Ruffman Physics Game - Early Comp

This is a for 5-8 year-olds with a physical science curriculum.
I created a quick comp for a pitch document. It also serves as a sort of colorful wireframe to help the team start to decide on buttons and layout.
This is the first attempt I've made at a final layout. One important constraint is that this game needs to work on screens all the way down to phone sizes.