Wall mounted ball run. This would be great for kids who are too young for the marble runs. Could be used as a music installation if there are movable obstructions in the pipe that make sound when a ball touches them
29 FUN Crafts For Kids That Adults Will Enjoy Doing Too Balloon rockets! -- 29 creative crafts for kids that adults will actually enjoy doing, too! If you appreciate arts and crafts a person will love this site!
Baby sensory play for a 6 to 9 month old baby. Wrap cling wrap around a canvas and have the baby smoosh away with their hands and feet. So much fun, but I'd do it without the Cling wrap! Edible paint and babies are washable!