1. STEM Project Safe in the Sun

2. Why is Sun Screen Important?

3. STEM Project Safe in the Sun  The sun produces lots of different types of rays, some you can see and some you can't  It is some of those you can't see that do the damage

4. STEM Project Sun Screen  A bottle of sun cream does not contain just one substance.  It is a mixture of lots of ingredients, each doing an important job.  One of the main ingredients has the job of stopping too much harmful ultraviolet from reaching the skin.  But, there's problem!

5. Safe in the Sun Activity 7 – Lumps or Powder?

6. STEM Project Grant is one of our scientists  In our factory we make an ingredient that is used in sun protection cream.  When this ingredient is made it’s in the form of big white lumps, but we cannot use these lumps in our recipe.

7. STEM Project Lumps or Powder?  When this main ingredient arrives from the factory where it is made it comes as large lumps.  To make the sun cream, however, this needs to be a powder, like this photograph shows  Why do you think it needs to be a powder?

8. STEM Project Lumps or Powder  The powder in sun screen is expensive, so we’ll use different types of sugar in oil  You need to predict & test which type would be best for a sun screen  How will we make our experiment a fair test?  Who will do what in your groups?

9. STEM Project Roles & Responsibilities  Administrator keeps a written and pictorial record for the group  Resource Manager collects, sets up and returns all equipment used by the group  Communications Officer collects the group’s ideas and reports back to the rest of the class.  Health and Safety Manager takes responsibility for the safety of the group, making sure everyone is working sensibly with the equipment  Personnel Manager takes responsibility for resolving disputes within the group and ensuring the team works together

10. STEM Project You will need  4 plastic cups of different types of sugar  Cubes  Caster  Granulated  Icing  4 plastic measuring cups with red lids  4 plastic spoons  1 timer

11. Safe in the Sun Activity 8 – Grinding Solids

12. STEM Project Grinding Solids  As we know, the sun screen active ingredient arrives in lumps and needs to be ground into a powder  Can you find the best material to grind up sugar lumps into powder?  How can we make it a fair test?

13. STEM Project You will need  Marbles  Ball bearings  Smarties / beans  3 pots with lids  3 sugar cubes  Weighing scales (shared between the class)

14. Safe in the Sun Activity 9 – Testing Sunscreens

15. Testing Sunscreens

16. STEM Project You will need  UV beads  Small samples of sunscreen A, B and C  Tray  3 Plastic cups  Teaspoon  Pipette

17. Product Protection