Make a life casting

What can I use if alginate or plaster of Paris is hard to find?

If alginate is unavailable, substitute a skin-safe silicone molding putty made for body casting and follow its mixing/curing instructions instead of the alginate steps, and use dental stone as a substitute for plaster of Paris when pouring into the mold for a stronger cast.

What should I do if the alginate is lumpy, the mold tears, or the plaster has air bubbles?

Remix the alginate in the bowl until smooth before pouring into the clean plastic container, apply a thin layer of petroleum jelly to the skin and keep the hand perfectly still until the alginate sets per the package time, then pour the plaster of Paris slowly into the alginate mold and tap the container lightly to release any air bubbles.

How can I adapt the activity for very young children, older kids, or teens?

For preschoolers have an adult do the alginate mold and plaster pour while the child watches, for school-age children let them measure and mix alginate and plaster with supervision, and for teens let them complete all steps (mixing, pouring, tapping, and decorating) and then share the finished creation on DIY.org.

How can we personalize or extend the finished plaster cast?

After the plaster hardens and you carefully remove the cast from the alginate, sand smooth, paint with acrylics or add colored plaster layers when pouring, attach a ribbon or hook for hanging, and seal with clear varnish before sharing on DIY.org.