By making a UV-meter you can test how well your (homemade) sunscreen blocks ultraviolet (UV) radiation from the sun. Ultraviolet waves are invisible, but are always around us. How can you make them visible? Follow the instructions from the download below and make your own UV meter.
A4 Instruction leaflets
Download the DIY instructions above. Print these double-sided (always the most sustainable choice) on plain paper. Now fold the paper twice, leading to a small booklet with the title in front. Ready!