This may well be my favourite activity to do with kids in the spring. We are aching to get our hands into the soil, so playing with clay and compost muck to shape seed balls is the perfect thing. And this takes lots of hands to get it done, since the "recipe" makes a huge batch! We made over 140 seed balls. Our recipe was not exact - approx. equal parts clay and compost, and enough water to make a good sticky mix that holds a ball shape. The wetter the mix, the longer it will take to firm up and dry fully. Plus enough seed packages to get a large number of seeds distributed into each ball. The idea is to fill the mix with seeds that are held in safe keeping until they have the right conditions to germinate - the clay protects the seeds, the compost is there to feed the seeds once the seed balls are tossed onto the ground and rained/watered to break them open. We seeded our mix with a bird/bee/butterfly pollinator mix of perennial and annual seeds saved from our garden (bee balm/wild bergamot, poppies, new england asters, black eyed susan, purple coneflower, butterfly weed, borage, eastern columbine, forget-me-not, coreopsis, lemon mint, lupines, and more).