STEM ED/CHM Nanotechnology
Teacher Guide for the Ultra Violet Sunscreen Protection Activity
The activity has been adapted from the NanoSense Curriculum Series available at:
This website includes several other related activities, PowerPoint slides, etc. However, their procedure differs in that they use color guide tube values in their data tables for the samples, without referring to the controls. We use a UV color guide and compare the test bead and a control to the guide colors. The guide can be downloaded from our web site and printed on an ink jet.
1. Safety. Be sure to either provide sunglasses that absorb ultraviolet radiation for the students or provide clear guidelines about pointing the ultraviolet light source directly down at the materials being analyzed.
2. Liquids. It is easy to get too little of a liquid on a bead since they are very slippery and the liquid can rub off as you spread it. This may lead to incorrect results. Try a light circular motion to spread the lotions evenly over the surface of the beads that are used to detect ultraviolet radiation. Alternatively, lotions can be put on pieces of clear plastic placed above the bead.
3. Materials purchasing
Source: Educational Innovations (
- We used a portable UV light - 1 (#UV-635, $10.95 each). It seems to have been replaced by #UV-640, $11.95 each
- Purple UV beads -1 set (#UV-PUR, $6.95 per 250 bead package)
- Clear UV blocking plastic disks - 1 set (#FIL-235, $14.50 per set of two discs)
- Bulk quantities of mixed color beads and rawhide are also available.
4. Making the beads into testers
To make the beads into bead testers you will need to melt them and glue them to wooden craft sticks. This makes them much easier for handling and applying sunscreen:
1. Preheat oven or toaster oven to 300ºF.
2. Cover a cookie sheet with aluminum foil.
3. Arrange beads on the cookie sheet. Place them one inch from each other and make sure they are laying flat on the sheet.
4. Place beads in oven and set timer for 15 minutes.
5. When 15 minutes is over, the beads should have melted and now look like clear discs.
6. Remove from oven to cool. They will harden to white discs within five minutes
Examples of Web Sites
- EPA UV index http://www.epa.gov/sunwise/uviscale.html