Materials List: white board or chart, student class mirrors, flashlights, Mirror Magic BLM
When light hits a surface, the light rays bounce or reflect off of that surface. Light rays reflect best off of flat, shiny surfaces. Mirrors are made of very flat glass with a shiny coating on the back. The sunlight penetrates the glass and hits the shiny coating on the back of the mirror and “bounces” or reflects off of the mirror. In this way mirrors can be used to change the direction of light.
Facilitate a discussion using the following prompt: “How do mirrors work?”
Investigation Task: Divide students into pairs. Give each pair a mirror with which to explore. Remind students to never look directly at the Sun, even when it is reflected in a mirror. List the following possibilities on the white board or a chart:
· Mirror Writing – put a piece of paper in front of a mirror. Look in the mirror and carefully write your name or message on the paper. The writing will be in “code” unless it is read using a mirror.
· Sun Catching – catch the Sun’s light and send signals.
· Eye-Spy – position the mirror to see around the edge of a corner or desk.
· Flash! – shine a flashlight into the mirror and see the beam reflect back.
To demonstrate understanding, have students illustrate light hitting a mirror using the Mirror Magic BLM provided. Have the students use arrows to depict the direction the light is traveling. The illustration should demonstrate the light source, the light “bouncing” off of the mirror, and the change in the direction of the light.
Once students have completed exploring with mirrors, facilitate a group discussion of the observations made during the investigation. Facilitate a discussion of how students believe a periscope works. If time permits, build a periscope as described in the book, Great Experiments with Light, listed in the Resource section.