This is a fun project for kids ages 5 to 15. Let them make paperweights from rocks they have collected.

Rocks, 1 per each paperweight (we find thin flat ones for this project)
Acrylic paint
A piece of felt fabric

Let the kids collect a rock they want to paint. Let them paint the rock with the acrylics. When they are done, cover the bottom side of the rock with a piece of felt fabric or other similar fabric to prevent the rock paperweight from scratching tables.