If your child marvels at the hues that she sees in a rainbow or always asks why the sky looks blue, activities on color and light can help her to explore these -- and other similar -- concepts in depth. Whether you have a preschooler who is just beginning to discover the scientific process or a sixth grader who is ready for more in-depth experiments, color and light activities are easy to adapt to almost every age.
Discussion and Vocabulary
Before the explorations and experiments on colors and light begin, starting with a discussion activity can help your child to better understand the concepts at hand and build a new scientific vocabulary. Even children as young as the preschool years can use "real" science words. Avoid dumbing down the terminology and introduce words such as wavelength (the distance between high and low points in a light wave) and visible spectrum (the colors that you can see with the naked eye). Hit on key points such as light transfer through reflection, absorption and transmission as well as how color is dependent on the type of light that meets the eye. You may also want to talk about light and shadow, the color wheel and the difference between visible and non-visible light.
Prisms, Visible Light and Color
Help your child to understand the visible light spectrum and how he is able to see certain colors. You will need a light source such as the sun or a flashlight, a white paper or index card and a prism for the most basic type of experiment. Children in preschool and the early grade school years can hold the prism up to the light sources (remember to avoid looking directly into the light) and allow a visible rainbow of colors to form on the paper or index card. You may need to hold the paper for your child so that he can move the prism or the flashlight. Have your child name the colors, in order from top to bottom or bottom to top, that he can see. Older kids can try varying the angle of the light source or the prism to create more or less visible colors.
Transmission, Absorption and Reflection
Light might move through a prism, but it doesn't always go smoothly through every object. Show your child how some objects can stop light from moving by absorbing it, some can reflect it and others can let it pass through. Hold a flashlight up to a piece of solid construction paper or card stock. Ask your child to explore and explain what is happening to the light. Swap out the solid paper for a piece of colored cellophane or acetate. Hold the new material up near a wall and shine a light source at it. Watch as the light goes through the cellophane or acetate and casts a colorful image. Next try turning off the overhead light and shining a flashlight on a mirror. Explore what happens when an object reflects the light.
What happens when we mix the colors that we see? Help your little learner experiment with color mixing to get a grip on how she can create new ones. The science experts at The Franklin Institute note that pigment colors, such as the artist's painted color wheel, differs from light colors. The three primary pigment colors are red, yellow and blue. When your child mixes these colors of paints she can make the secondary colors of green, orange and purple (yellow and blue make green, yellow and red make orange, and blue and red make purple). The primary light colors are red, blue and green, which mix to make the secondary ones of yellow, cyan and magenta. Experimenting with the light colors is often tricky for the young child. You can use discussion and even make a color comparison chart to show your child how mixing differs depending on what colors she is using.