As you can see I bought a couple of LEGO bases. They are 10x10 inches. I had my husband cut a couple of 12x12 inch boards. I painted each to match the room and glued (with a strong adhesive) the base to the boards. I bought blocks to match his color scheme from the LEGO store at the Mall of America. If you look on the green, painted square on the right you will see 3M's velcro command strips. I have found out that the strips do not stick well to fresh paint so I think we are going to switch to framing teeth.
Anyway, I think these were pretty successful and I think Sawyer likes them too!