Earth Science: The Sun's Power (Sunscreen Experiment)

Sunscreen Experiment

Standard: ALEX (3^RD Grade) - 3.) Describe ways energy from the sun is used.

Examples: plant growth, light, heat

• Identifying fossil fuels as a source of energy

FOCUS QUESTION* (Big Idea)

What do you have to investigate or figure out in this lesson that is related to the big idea?

What will be the main question that will guide your learning?

Why do we wear sunscreen? How do you think sunscreen protects our skin? Does it completely protect our skin?

PREDICTION/ HYPOTHESIS*

What do you think will happen (USING PRIOR KNOWLEDGE)

If I do … then… will happen because…

I think … because

I think the sunscreen with more SPF will show as more protective for our skin.

PLANNING

  • Lists the materials

  • Describe in simple steps you take so someone else can repeat the experiment & get the same results

1 Sheet of 81/2” x 11 clear plastic acetate

Black permanent marker

Three “protection levels” of sunscreen SPF 0, 8, 15 and 45.

Photoreactive paper

Plain cookie sheet

9x13 Pyrex dish of water

1.)   Explain to students that they will be looking at what is really happening when they smooth sunscreen onto their skin.

2.)   Take the clear plastic sheet. Draw a straight line vertically and horizontally through the middle of the sheet making four different “panes”. Mark one SPF 0, another SPF 8, then SPF 15, and finally SPF 45.

3.)   Measure about ¼ teaspoon of each kind of lotion and use your finger to smooth it carefully over its appropriate “pane” on your plastic. (Remember one pane will have no sunscreen at all).

4.)   Quickly remove four pieces of photoreactive paper from their protective envelope, place them on the cookie sheet, and then cover them immediately with the plastic sheet you just prepared.

5.)   Place the cookie sheet in full sun, with no parts shaded, and leave it there for 1-4 minutes, or until the SPF 0 pane looks nearly white.

6.)   Bring sheets inside, carefully take the plastic sheets off, and use your marker to write its correct SPF. Then rinse the papers in the water tray and remove to observe.

 DATA*

Record the data in a way that will make sense to you later:  

Paragraph, Bullets, Table/Chart, Drawings, Graphs, etc.

Title and label diagrams and pictures

	Predictions	Results
SPF 0	There will be no protection because there is no sunscreen.	This one had the most exposure to the sun. It turned white as the sun hit it.
SPF 8	This one will be the least protective besides no sunscreen.	This one looked white, but it looked like water. It might not protect us for as long because it looks thin.
SPF 15	This will be the second best sunscreen to protect our skin.	This one was the whitest. It looked thicker than the others and had less blue coloring showing through the sunscreen.
SPF 45	This will be the best protection for our skin.	This one showed the color blue all over and less white.

CLAIMS AND EVIDENCE*

State your claim based on your evidence (data collected from observations)

What do you claim to be true?

How can you prove what you are stating? (Back it up) 

I claim that when ………, then ……….. (happens)….

I know this to be true because I observed………

I claim that the higher the SPF, the less we see the color of the paper change to white. I know this to be true because I observed the sun changing the color of the paper more with lower SPF.

CONCLUSION*

**Restate the focus question as a topic sentence

In this investigation…   

In this inquiry….

I (we) learned that…..

Use details from your claims and evidence (data) chart to answer the focus question.

 **Every claim must be supported by evidence. 

I (we) liked/did not like…… because

My (our) prediction that…..was…..because….

This reminds me (us) of….. because….

I (we) discovered that…..

Now I (we) think that….because

**Refer back to your hypothesis

My hypothesis was correct/incorrect because…

**Record your thoughts after the experiment   (Understandings, Likes, Related Thinking, Connections)

**Include a summative sentence that can be a restatement in different words of the topic sentence.

**QUESTIONS:   What new questions do you have to extend your learning?

Does a swimsuit or shirt that we wear outside work better than sunscreen? If we were to use tanning oil/baby oil instead of sunscreen, how would that affect our skin differently? Claim & Evidence:

We claim that SPF 15 had the most protection from the UV rays because it had the most white.

Conclusion:

We learned that the higher the SPF does not mean the more protection from the sun.

 Questions:

Do animals get sunburned?