Year 3 – 4 | Sunglasses Experiment – UV Reactive Beads

Protecting My Skin full resource download  |  Concept 2: Heat and UV from the sun: What’s the difference? download

Background

In this lesson, students will observe the effects of UV radiation. The UV reactive detection beads indicate UV light by
changing colour. The stronger the ultraviolet (UV) radiation present, the quicker the colour change and the deeper the
colour. Once indoors and away from the sun’s ultraviolet light, the beads change back to off-white. The sunglasses and UV
reactive beads experiment tests to see if sunglasses can block out UV radiation.

Key messages

• UV is invisible, you cannot see or feel it. We can see its effects though. If the UV Index is 3 or above, it can cause sunburn
  and skin damage.
• When the UV Index is 3 or above, sun protection is required.
• UV and heat are not the same thing. It is not only when it is hot that we need to use sun protection. The UV Index can be
  3 or above when it is cool and cloudy too.
• UV radiation can bounce and reflect off surfaces, so it is important to use a combination of sun protection strategies.
• The UV Index is an open-ended numerical scale that measures the amount of UV radiation reaching the earth’s surface.
• The UV Index shows a daily time period indicating the strength of UV levels and peaks normally at solar noon on a clear
  sky day. Solar noon is the point at which the sun is directly overhead.

Resources

• UV detection beads
• UV torch (optional to sun light)
• A range of sunglasses lenses (donations)
• Two small containers per group

Instructions

Experiment: To test if sunglasses can block out ultraviolet (UV) radiation.

1. Prior to the experiment, students make predictions and suggest outcomes and reasons.
2. Place 6 beads into two small containers and cover each with a sunglass lens.
3. Place the containers outside in the sun and remove the lens from one container. Leave the other container with the lens
   covering the UV beads.
4. Leave for one minute and then compare the colour of the beads.
5. Students record observations and results, then present findings
6. Class discussion: Prompt students with key questions to help them develop an explanation for the changes they are
   seeing in the UV beads.
7. Students complete the following unfinished sentence. Using a sunglass lens…
8. Students share their findings. What did I learn?

Key questions

• What do you notice about the beads?
• What colour were they before? What colour are they now?
• What effect did the lens have on the colour change of the beads?
• Are all the beads changing colour? If not, why not? If so, why do you think they are?

When completing activities and lessons outdoors when the UV Index is 3 or above, please remember to be SunSmart