Fluorescent toys

Use a UV light to look at fluorescent pens, toys etc. Some rocks are also fluorescent.
Science content
Chemistry: Atoms, Molecules (3-7)
Chemistry: Chemical Changes (2, 7)
Physics: Light and Sound (1)
Physics: Energy forms, Conservation of Energy (1, 3, 4, 5)
  • darkened room e.g. behind the curtains on the school stage
  • UV light
  • fluorescent pens, toys
  • optional: fluorescent rock e.g. calcite

When you shine light on these items they glow. The UV light gives fluorescent molecules extra energy. They release this energy again as light.
(Older students: discuss how electrons move to a different energy level when excited by the UV light, then release photons of a different colour light as they return to unexcited state).

Fluorescent markers only glow when the UV light hits them - the fluorescent molecules release the light energy right away.
Glow in the dark object release light after the UV light is taken away - the "phosphorescent" molecules in them release light slowly.

Some rocks are fluorescent. See photo of calcite fluorescing pink.

Grades taught
Gr 1
Gr 2
Gr 3
Gr 5
Gr 7