8. Electronics. Voltage, resistance, current, and blinky lights. Battery-powered toys (hack them), 9-volt batteries (lick them), LED throwies, introductory electronics kits.

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10. Energy. Conservation and momentum, transformation (one type to another), generation, storage, consumption. Marbles, batteries, rubber band-powered airplanes, bicycles, dirt bikes, cars, slot cars, train sets, swings, skateboards, kites.

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A Curriculum of Toys

Great list of practical toys and tools to learn about the world around us.