Here is a quick tip that I would like to share after building a couple of Tiny Trainers with my young boys. It was difficult for them to peel the waste foam out of "A" and "B" folds and at the edges of body panels. I had scored the foam-board paper, but it was difficult for them to cut the remaining foam with a hobby knife without cutting the paper on the other side. So, I made wooden knives out of popsicle sticks, as in the attached photo. They are easy to carve out with a knife and sharpen with sand paper. You can form the blade shape to your preference and customize it to the task. The result is sharp enough to split foam but not cut through the paper backing. That makes it great for peeling foam waste out of joints and for creasing along score lines. It is also much safer than a knife for these operations, which was a welcome advantage with the young ones.