The Fridge Magnet Marble Run is a great toy for kids and big kids to stick on the fridge and play with. It was designed in prodesktop, and can be cut out with a laser cutter, using 3mm material. You can use marbles or coins, the coins will run much slower and require steeper incline than marbles, but still fun to set up and play with. A friend suggested I put a box at the bottom that you cant get into for the coins.
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