Ok, this one might be just for the girls in the house.
Cut out several tracings of your hand, making sure to draw finger nails on each of them.
Set up a mini nail salon with your finger nail polish and a little table, and let your child go to work.
I would recommend doing it away from carpeted areas. Not that you wouldn't have thought of that on your own.
(Tia treated each hand like a real customer and asked them what colors they would like on their nails today.)
Try this with toes too!