DS21mo loves jigsaw puzzles, and he has been doing wooden jigsaw puzzles.

His latest favorite is the US map puzzle: http://www.amazon.com/Melissa-Doug-Wooden-Jigsaw-Puzzle/dp/B00000JBLI

He has a couple of Melissa and Doug 24-piece ones that are no longer challenging for him, so I bought some 48-piece ones. But he is not interested in them because they are not themes that he cares for.

He loves cars and trains. Any ideas for car or train jigsaw puzzles that are either wooden or printed on thick cardboard? I prefer something more than 24 pieces if possible.

P.S. I think we have owned all the Melissa and Doug car/train puzzles. LOL.

Thanks!