Lesson Preview: Sunscreen Science
In our Lessons portal, Because Learning has over 130 (and counting) Lessons for your classroom. Check out a preview of our Lesson format with one of our most popular choices, Sunscreen Science!
Note: the buttons and fields don’t work on this sample. But when you access Lessons via our online platform, the interactive elements you see allow students to engage with the Lesson content.
There are a few things you’ll want to see:
- Our Experiment Guide at the bottom of the lesson is perfect for teachers (included with every lesson!)
- The steps in the experiment below can be customized to fit your class’s specific needs, making our lessons flexible
- This isn’t just a “follow these steps” lesson – it’s an interactive experience for your class!
- If you like what you see and want to chat about bringing Because Learning to your school, request a demo!
Let’s begin the Lesson preview!
Sunscreen Science
Do more expensive brands of sunscreen protect from UV radiation better, worse or the same as less expensive sunscreen?
Step 1: Gather Supplies
What you’ll need for this experiment:
- Sensor Kit
- Plastic wrap
- Permanent Marker
- Sunscreen with one variable. Suggested variables are:
- Same SPF, different brands
- Same SPF, same brand, different type (lotion, spray, stick, etc)
- Same SPF, same brand, different expiration dates.
Step 2: Background Information
What is UV light?
We all know that the sun produces light–scientists call it electromagnetic radiation. The electromagnetic radiation that is produced by the sun is made up of a bunch of different wavelengths. Only a small portion of the wavelengths can be seen by humans. We call this small portion visible light. The picture below shows the electromagnetic spectrum:
This diagram of the electromagnetic spectrum arranges the electromagnetic radiation by wavelength. At the far left end of the diagram is the electromagnetic radiation that has a long wavelength called infrared light (or IR for short). At the far left end of the diagram is the electromagnetic radiation that has a short wavelength called ultra-violet light (UV for short).
Some living creatures are able to see UV light with their eyes. Bees use UV lightto help them navigate to the best flowers from which to collect pollen. The short video clip below illustrates how bees use UV light:
When human skin is exposed to sunlight, it either burns or tans–that is because UV light has a short enough wavelength to break the chemical bonds in skin tissue. Too much exposure to sunlight and UV light can cause serious, irreversible skin damage–which is why sunscreen is so important!
Sunscreen works by scattering and absorbing UV light. When you put sunscreen on, it is like putting on an invisible barrier that prevents UV light from penetrating your skin.
Step 3: Experiment Setup
For this experiment, you need to decide what you are testing and what your question is going to be. Three suggestions were given above in the materials list.
- Same SPF, different brands
- Same SPF, same brand, different type (lotion, spray, stick, etc)
- Same SPF, same brand, different expiration dates.
You can pick one of these or you can devise your own experiment. Remember, each sunscreen has at very minimum 3 variables:
- Sunscreen Brand
- SPF Number
- Expiration Date
Pick one variable to change and test and keep the others the same–these will be your constants. For example, I would like to test expiration dates.
- My question is: Does expiration date affect how well sunscreen blocks UV light?
- My variable is going to be the expiration date.
- My constants are going to be SPF number and brand.
In other words, the sunscreens I am testing are the same brand and SPF, but they have different expiration dates.
Now it is time to make your prediction or hypothesis.
Step 4: Experiment Procedure
1. To setup your experiment, you need to get a piece of plastic wrap and mark as many squares on the plastic wrap as you have sunscreen to test, you should also have one square that doesn’t have any sunscreen–this is your control.
2. Label each square with the name and SPF of the sunscreen you are testing and then dab a bit of each sunscreen in the proper square. Spread out until the entire square is covered.
Note: Your squares should be slightly bigger than the Sensor Board.
3. Wire up your Sensor Board using the diagram below:
4. The code block below tells the microcontroller to access the Ultra Violet (UV) sensor. Plug in your microcontroller to your computer with the USB cord and press the “Run on Arduino” button.
5. To access the UV data, click on the “Connect to Arduino” button below.
6. Take your sunscreen plastic wrap, your Sensor Board, and your computer outside. Test each square on the plastic wrap by placing the sensor board underneath the sunscreen smeared plastic.
7. Record your data in your lab notebook.
Step 5: Conclusion
Use your lab notebook and the data you collected to draw a conclusion. What does the data tell you?
Now that you’ve tested one variable related to sunscreen and UV readings, try repeating the experiment and see if you get the same results. Science is all about making sure the results from an experiment are repeatable over many tries.
Or, how about a new experiment altogether? Pick a different variable to change from the suggested list above? How would you set up that experiment–what would you need to control and what would you need to vary? Head on over to our UV Sensor guide to gather UV readings and data.
Did you like the Sunscreen experiment? Try following our experiment guide for testing cost vs effectiveness of sunglasses–Sunglasses.
Now try this!
To access more information about this experiment such as NGSS alignment, pacing, essential questions, and inquiry-based teaching practices, check out the Experiment Guide.
If you are stuck and need help check out our troubleshooting tips and help center.
Join our Sunscreen Science Community Discussion to connect with the Learning Team or to discuss experiment tips, ask questions, leave comments, or suggest experiment variations.
Photo Credits:
UV and Visible Light Portrait by Spigget (Own work), via Wikimedia Commons
Electromagnetic Spectrum: Science Kids at Home
Sunscreen gif: Giphy
We Have 130+ More Lessons Just Like This
That’s the end of the Sunscreen Lesson, but it’s not the end of our curriculum! We have over 130 Lessons organized by subject, grade level, sensor, and unit.
Best of all, these Lessons fit into your curriculum and enhance your STEM teaching efforts! Contact us to learn more about bringing better STEM learning experiences to your students.
