Cant get back to home screen

I bought this for my autistic 3 yr old and went to try it out. When it first opened it offered all shapes or specific category, I chose all and after seeing words/shapes like mandolin ....I decided he would do better starting with a food category only. Well, it wont go back to the home screen! It is stuck in this mode. Please fix this and think about adding the option of deleting odd shapes or cards.

Valerie1461 about ShapeBuilder Preschool Puzzles, v1.3