Hello, I am new here & I'm looking for train board ideas that are not made of wood. I would like it to be around 4 x 5 to 4 x 8 in size. What would be a good material to buy? Foam? Cardboard? or anything else. Also where would I go to purchase these types of boards? This will be something I'm doing for my 5yr old son who just got his first electric train set. Thanks to you all for the help!