How-to: Homemade Sidewalk Chalk

NOTE: Don’t you dare pour any unused plaster of Paris down your drains! You can take containers outside and rinse them out with your garden hose, or wait until the plaster has set on a container and then chip it off, but in our house we tend to use stuff that’s on its last legs, anyway–the cups that came with our take-out pizza, old paint stirrers or sticks from the yard, rinsed-out deli containers, etc.

In the same vein, don’t wash your molds until you’ve thumped off all the dried plaster around their edges. Cardboard molds can be dropped back into the recycling bin, but if you’ve cut up a recycled plastic mold so much that it no longer has its recycling number on it, you’ll likely have to toss it in your regular trash.

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