Making sun prints is a fun science experiment and this twist adds letters and numbers to make it a learning activity as well! 
Sun Prints Numbers & Letters Video
Check out the below video to see the activity in action:
Materials Needed (aff links)
- Baking sheet
- Dark colored construction paper
- Magnetic letters and numbers
What To Do:
- Start by placing sheets of dark construction paper on a baking sheet.
- Next place magnetic letters and numbers on the paper and place out in the sun.
- Optional – If it’s a windy day, secure the corners of the paper with small bits of tape or be sure the magnetic letters are placed near the corners.
- Wait for 2-3 hours then remove the letters and numbers to reveal the prints underneath.
Why It Happens
The sun emits UV (ultraviolet) light waves down onto the earth and these waves carry enough energy to break the bonds of some chemicals, like the dyes in the construction paper. This causes the color in the paper to fade. When the letters and numbers are removed, those parts of the paper remain fully colored since they were protected from the UV light waves. This experiment is a good reminder of why we need to wear sunscreen on sunny days. The UV light waves can also damage skin.
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