I love this idea. I didn't have a lot of resources growing up and my family still found ways to keep me creatively engaged: building kites with my grandma, making lava lamps with my cousin, or simply building forts by myself. Whatever the scenario, the thing that kept me engaged the most was problem solving...such as, "How do I make a fort that has a secret room or a trap door?"
I wonder if your kits might contain unique, actionable problems to solve...something like, "Create a self portrait using whatever is around you" or, "How might one get to Mars?"...in either case, you would be providing a starting point for creativity by proposing a problem with no specific endpoint.
Sometimes creativity is just blocked by not having a place to start.