Shadow Theater

The big ideas

What the levels teach, in grown-up words.

• A shadow is where light is blocked. Light travels in straight lines. Where an object stops it, the surface behind stays dark, and the dark patch has the object's outline.
• Shadows move the opposite way from the light. Move the lamp left and the shadow slides right. Lower the lamp and the shadow climbs the wall.
• A close light makes a big shadow. The shadow is the object scaled up around the lamp. If the lamp is twice as far from the screen as the object, the shadow is twice as tall.
• The sun is a lamp that moves. Low morning and evening sun makes long shadows; the high midday sun makes short ones. A sundial reads the time from the shadow.
• Two lamps make colored shadows. Where an object blocks only the red lamp, the blue lamp still lands, so that shadow looks blue. Where both are blocked, it is dark.
• Big lights make soft shadows. Every point of a big light source casts its own shadow, and the edges overlap into a blur. Materials are opaque, translucent or transparent depending on how much light gets through.

Try it at home

Quick experiments that match the game.

1. Flashlight theater. In a dark room, stand a toy in front of a wall and shine a flashlight at it. Move the flashlight closer, farther, up and down, and talk about what the shadow does.
2. Shadow puppets. Make a bunny or a dog with your hands between the flashlight and the wall. Try it with the light close and far away.
3. Chalk the shadow. On a sunny morning, trace a friend's shadow with chalk. Come back at lunch and again before dinner and compare.
4. See-through sort. Collect a book, a plastic bottle, a leaf and a tissue. Hold each one up to a window and sort them into blocks light, lets some through, and see-through.