Call me corny but I've always wanted to try spray painting with a cutout stencil starting with my man cave (our former team hangout haha) the garage. I don't necessarily have to make it a garage or car theme but perhaps a basic panoramic cutout of NYC or something.
Now maybe for your little dude you can do something like dinosaurs, uhum cars, random shapes, Disney characters, etc...
RE: Sunday Means Family Day