lets you experiment with basic electricity. It includes worksheets that cover a variety of topics (including circuits, flashlights, doorbells, motors, batteries, dimmers, fuses, series lamps, and parallel lamps) along with example designs.
You can also set up your own circuits by dragging and dropping batteries, fuses, switches, resistors, buzzers, filament lamps, LEDs, and motors onto the drawing area. Then link them by drawing wires between their terminals. As you draw, the animation shows the design springing to life. You'll see motors turn, lamps light up, etc.