Shadow Shapes
Concepts and skills: Fine motor skills, physics, optics, light, shadow, reflection, absorption
Recommended ages: 3 and up (adult assistance recommended)
Materials:
Paper
Scissors
Tape
Craft sticks
Flashlight
Chair
What to do: Use scissors to cut different shapes out of paper and tape each shape to a craft stick. Place a flashlight on a chair and shine it on a wall about 4 feet away. Place shapes in between the wall and the flashlight to project its shape on the wall.
Investigative questions: What shadow stories can you create with simple shapes? What happens when you move the shape closer to the flashlight? What happens when you move it closer to the wall? How does the shadow change as you turn your shape?
Tracing your Shadow
Concepts and skills: Earth's place in the universe, light, shadow, reflection, absorption
Recommended ages: 5 and up
Materials:
Chalk
Sunshine
Sidewalk or Driveway
What to do: During the morning or early afternoon, find a sunny spot on a sidewalk/driveway. Have a friend or adult use a piece of chalk to trace your shadow on the ground. Observe your shadow every hour to see how it changes over time.
Investigative questions: How do shadows change throughout the day? What does this tell us about the position of the sun and its movement throughout the day?
Rainbow Investigators
Concepts and skills: Physics, optics, light, shadow, reflection, absorption, refraction, rainbow, spectrum
Recommended ages: 5 and up (adult assistance recommended)
Materials:
Black paper
Scissors or hole punch
Tape
Multiple reflective materials (mirrors, aluminum foil, glasses with lenses, water in glass cup)
Flashlight
What to do:
1. Use scissors or a hole punch to cut a small circle in the black paper so that the hole sits right over the flashlight. Pull the paper over the head of the flashlight and tape the ends of the paper down to the body of the flashlight, so only a little bit of light can escape through the small hole when you turn on the flashlight.
2. Explore your home for reflective surfaces. Can you get your light beam to reflect off of multiple surfaces at the same time?
3. Investigate what happens when you shine your light beam through a glass of water or off of a mirror.
Additional Information: Certain materials can refract or bend white light so that the 7 colors of ROYGBIV that make up white light are visible. Water, mirrors, and prisms are great materials to help make white light spread into the different colors that our eyes perceive as white when they are all together.
Where else have you seen a rainbow or visible color spectrum? What materials helped make that rainbow?
Spectrum Shapes
Concepts and skills: Light refraction
Recommended ages: 4-8
Materials:
CD
Paper
Scissors
Flashlight
What to do:
1. Cut the paper into a circle the same size as the CD.
2. Cut shapes out of the paper.
3. Tape the paper onto the iridescent side of the CD.
4. In a dark space on a table, stand the CD on its side and shine a flashlight at the iridescent side of the CD. Observe the reflection on the table.
Additional Information: When a light wave travels through an empty space it travels in a straight line at light speed. Once that light wave starts traveling in different materials it slows down and bends, this is called refraction. Different colors have different wavelengths. When they get refracted they bend different amounts causing the colors to spread out, these are called spectrum.
Some materials light will travel though, these are called transparent. Some materials light can not travel through these are called opaque. Some opaque objects can reflect light.
When we shine a light at the CD the plastic refracts the light and the metal on the top reflects it, causing spectrum to form. Paper is opaque. When we put it on the CD it stops the light, only the exposed parts create spectrum.
Make Your Own Magnifying Lens
Concepts and skills: Light refraction
Recommended ages: 5-9
Materials:
Plastic bottle with the bottom cut off
Flexible clear plastic sheet (such as a plastic sandwich bag)
Rubber band or tape
Water
What to do:
1. Place the plastic sheet over the open bottom of the plastic bottle.
2. Secure the plastic to the bottle with tape or a rubber band. The plastic sheet should not be pulled tightly—there should be some flexibility after it is secured.
3. Add water to the bottom of the bottle (just enough to cover the bottom layer of the bottle). The plastic on the bottom of the bottle should form a curve.
4. Hold the bottle a few inches over an object and look through the top of the bottle. Observe what happens!
Additional Information: When a light wave travels through an empty space it travels in a straight line at light speed. Once that light wave starts traveling in different materials it slows down and bends; this is called refraction. Lenses are shaped in a way that when light is refracted by them, they focus the light at a specific point.
There are two types of lenses: convex and concave. Concave lenses are wider at the edges than in the middle and create a focus point on the same side of the lens as the light source. Because the focus point is on the same side as the light source, we can’t actually see it, but we can see the light spread out when it goes through the lens. Convex lenses are narrower at the edges than in the middle and create a focus point on the opposite side of the lens as the light source. When looking through a concave lens, objects look bigger because of this change in the focus point. We made a concave lens in this activity.
