Here’s something fun to do with the kids tomorrow after they’ve finished emptying those big plastic eggs of jelly beans and malted milk balls.

The basic ingredients are plastic eggs, a small DC motor from an old CD player, and a cheapo multimeter. It’s a quick afternoon project, and you’ll be able to measure the wind’s speed—a useful addition to your toolkit for backyard experiments.

Easter Egg Anemometer (Wind Speed Meter)