Cyanotype Paper is safe fun for kids to try Sun printing silhouettes.

Another project is growing large salt crystals in saturated solution.

The Unitech Electric Static Wand Toy off amazon was also popular last year (poorly built mini Van de Graaff generator.)

Glow in the dark wall paint and a 5 second strobe light is also a classic silhouette demo.

Could also look for linear polarizing sheets, thermochromic sheets, and "Magnetic Viewing film".

Some will like this stuff, others only want to stare at a screen. =3

It’s fairly easy to make cyanotype yourself: https://simplifier.neocities.org/cyanotype

Thank you, those are some awesome ideas. We've tried about half of them, but the rest are going straight on the list. Much appreciated.