Thinking of different things I could offer, that are different than what parents already have access to.
How about: 6 weeks of weekly kits that include materials for
-sensory play and exploration: includes a new sensory material each week (slime, kinetic sand, etc)
-process art: includes art materials each week for different media, like: fingerpaints and fingerpaint paper, or assemble a wood picture frame and paint to paint it