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The humble pegboard can be used in a variety of ways. An all pegboard Rube Goldberg. Demonstrating the Cartesian graphing system. The limit to the usefulness of this board of holes is hard to measure.
Pegboard Rube Goldberg
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Simple construction with 2×4’s and 4 2’x4′ Pieces of pegboard.
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The lesson can be as simple as dominoes on inclined planes.
Watch this for an animation of virtual dominoes
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Or use whatever you can find around the garage.