Grades: 1 to 5
Duration: 1/2 Hour – 1 Hour
Supplies: A very dark closet or items to build one (blankets, large boxes), flashlights, construction paper, aluminum foil scissors.
Background and motivation
Begin a unit on light by having a classroom discussion that introduces the idea that light is what allows us to see. First, close the shades, cover the windows and turn off all of the lights. Then invite students to complete a task, such as coloring or reading. When they complain that they can not – ask them why? Ask students to brainstorm a list of dark places – cave, deep sea, movie theater… Ask student WHY those places are dark? Facilitate a conversation that leads students to realize that without a source of light, there is no light; and with no light, there is no seeing! Once students are clear that light is what allows them to see, introduce them to the idea that light comes from a source. Brainstorm sources of light – candle, light bulb, sun…
Build or find your cave.
Prepare a very dark “cave” in your classroom with blankets and/or boxes that students can easily climb in and block out light from the room. You can do this in advance, or have students brainstorm and create it with you, working together to make it as dark as possible. If you don’t have the time or the materials to build a cave, you can use an empty dark closet for this activity.
Make Paper Dolls
Use this template with construction paper and aluminum foil to cut out 6 paper dolls: 2 white, 2 black and 2 aluminum foil. Again, this is something you can do in advance or you can have students cut out the paper dolls.
Hide the Dolls
Place one doll of each color (white, dark and aluminum foil) inside the dark cave. The idea is that students will search for them without light and will not be able to find them. Place them on the floor, walls and even ceiling of the cave so they will have to look hard to find them.
Show students the dark, white and foil dolls and invite them to predict which doll(s) they will be able to see inside the cave (without taking a light in with them). Write down their predictions.
Test the prediction
Invite one or two students at a time to go into the dark cave without a light to look for the hidden dolls.
Soon, students realize, they can not find any dolls. Discuss what they predicted vs. what actually happened. Ask, why they found no dolls. What do they need? LIGHT!
Give each student or small group of students a flash light or LED and allow them to use the light to look for the hidden dolls. Discuss both their findings and the process of predicting, testing, changing a variable (light) and predicting and testing again. THIS IS SCIENCE!!