Teaching children about reflection is as simple as using a mirror and a laser pointer. Have one of the children stand a few feet away from you holding a small mirror. Turn on the laser pointer and point the laser at the mirror. Have the other children look for the red laser dot around the room. When they find it, have the child holding the mirror tilt it slightly. Now turn off the lights in the room and bang two chalk erasers together to create a dusty environment so the kids can see the path of the laser change. Explain to the children how the laser is a beam of light just like the light beams that come from the sun.
Have the children gather around your desk or a table and then take out a standard pencil and a glass of water. Have the children look at the pencil and watch it closely as you place it into the glass of water. They will see that the pencil appears to be broken. Take this opportunity to explain how light travels 25 percent slower through water than it does through the air. Because of this, the image in the water is refracted (bent). Now take a few pebbles out and place them behind the glass of water. Have children take turns trying to pick up the pebbles while they look through the glass. This is a concrete way to show them that light bends.
A simple way to look at properties of refraction is by using prisms. Distribute several prisms to your kids so they can experiment with them. Have them place the prisms near different light sources to produce rainbows. Explain how sunlight and incandescent bulbs have the entire visible spectrum in them and that a prism causes different colors of light to refract at different rates. This can lead to several different directions depending on the age of the children. Consider a discussion of ROY G. BIV (Red Orange Yellow Green Glue Indigo Violet); talk about the visible spectrum and what infrared and ultraviolet are; or start a simple discussion on the difference between a red laser light and sunlight.
Older children can play the prism game with a protractor, a laser light, a piece of poster board and a mirror. Mark the poster board with a bull's eye system, assigning points to different rings. Then have the children play around with the prism. mirror and laser for a while before starting the game. Explain that under the rules of the game, the prism and mirror must both be used to direct the laser beam at the target. The prism and mirror must be set up first and then the laser turned on. If the laser beam hits the poster board, the team (or individual) scores whatever points are in the area of the bull's eye that is hit. Start the first round at an easy five feet away and back up five feet for each subsequent round. After a determined number of rounds, the team with the highest score wins.