Create your own ornaments for a holiday tree, to decorate the home or to give as gifts. Plaster of Paris is readily available at craft and hobby stores. Easy to work with, it hardens quickly without the need for heat or special treatments. Use purchased moulds to shape your ornaments or pour the plaster of Paris into the bottom of plastic cups to make disk-shaped ornaments that you can paint with your desired design.
Prepare moulds and drinking straws before mixing the plaster. Set the moulds on top of a sheet of newspaper and cut the straws into 1-inch lengths.
Combine one part water with two parts plaster of Paris powder in a disposable bowl. Place the water in the bowl first, and then sift the plaster powder over the water surface slowly. Tap the sides of the bowl as you add the plaster so all the powder settles beneath the water surface.
Stir the plaster with a plastic spoon after it has set in the water for one to two minutes. Mix slowly until the plaster reaches a smooth consistency.
Set a straw in the mould where you want your hanging hole to be. Hold the straw in place with one finger, and then pour the plaster of Paris into the moulds, taking care not to get plaster in the straw opening. Tap the sides of the moulds so the plaster settles evenly in each mould.
Hold the straw in place for two to three minutes, or until the plaster hardens enough to hold the straw upright. Allow the plaster to dry for one hour.
Pop the plaster ornament out of the mould once the plaster is completely hard. Trim the protruding end of the straw so it is flush with the plaster.
Paint the plaster of Paris with your desired design using acrylic paints and a paintbrush. Allow the paint to dry and seal it with a coat of clear gloss acrylic. Loop a ribbon through the straw hole for hanging.
Mix poster paint with the plaster before pouring if you want to colour the plaster.
If kids are making the ornaments, make sure an adult supervises. Plaster of Paris may put off heat as it dries, which can cause burns. Do not pour plaster of Paris down the drain, as it will clog up plumbing.