A shadow is made when an object blocks rays of light. The shadow appears on the side of the object furthest from the light source. The Sun is a very bright natural light source. The sun’s position in the sky affects the size of shadows. The Sun casts the longest shadows at the beginning and end of the day, when the Sun is lowest in the sky. The Sun casts the shortest shadows at midday, when the Sun is highest in the sky. Even the moon can create shadows when it reflects light from the sun.
Light only travels in straight lines. Light can’t bend around corners or travel through most solid objects. When light is blocked by an object, a shadow is formed behind it. Opaque materials do not let any light pass through them. They block the light. Wood is an example of an opaque material. Transparent materials let light pass through them in straight lines, so that you can see clearly through them. Glass is an example of a transparent material. Translucent materials let some light through, but they scatter the light in all directions, so that you cannot see clearly through them. Tissue paper is an example of a translucent material.
Body Outline Shadow Painting: Have each child lays on a large piece of brown craft paper. Trace their body and cut out their outline. Place brown body outline on top of a large black piece of paper. Place flat rocks on top of outline to secure in place. Help children use a roller with bright paint to roll on edges of body outline. Then remove outline and you have a shadow of the child’s body outline painting.
Toy Shadow Tracing Experiment: Go outside and see how sunlight creates shadows with various objects such as trees, houses and cars. On a sunny day set a toy or interesting shape on a piece of paper in the sun. Trace the shadow with chalk or oil pastel every 20 minutes to see how a toy’s shadow (like our shadow) changes as the Earth moves around the sun. In the morning, the Sun is low in the eastern sky, so the toy’s shadow lengthens and points more toward the west. As the Earth turns, the Sun appears to rise in the sky and move west, making the toy’s shadow get shorter and move in the opposite direction. As the Sun sets in the west, the shadow points east and grows longer until it disappears in the dark. Add watercolor to finish artwork.