My 11 year old loves Memoir '44. It is 2 player WWII board game. Of course it has expansions. Which can be pricey since they sell the expansion game pieces and board separately. Long story short, B. used his own hard earned money to buy an expansion, but only the game pieces and he decided to make the board himself at the fraction of the price. Plus his is much sturdier, because he used thin plywood. He cut, sanded, painted and drew in the details. All on his own.
Here is a picture of the board you can buy (he made the winter board, the white one):