Paper mache builds a rigid hollow form by layering paper strips in adhesive over a shape, then removing the shape once the shell cures.
It predates every material on this list and it still has a real place — it costs almost nothing, needs no specialty supplier, and produces a hard, paintable, surprisingly durable shell.
The two pastes
Flour and water is free and works fine, but it attracts pests and can mould if the piece isn’t dried thoroughly. Diluted white glue costs a little, dries harder, and doesn’t spoil. For a puppet that has to last, use the glue.
The form underneath
A balloon for a simple round head. Crumpled newspaper and tape for a rough shape. Clay for a detailed sculpt you will dig out afterwards. Cover the form in petroleum jelly or plastic wrap first so the shell releases.
Layering
Three to four layers minimum, alternating direction, with each layer fully dry before the next. This is where beginners lose. Rushing a wet layer onto a damp one produces a shell that stays soft in the middle, warps as it finally dries, and cracks under handling. A good head takes several days of mostly waiting.
Finishing
Cured mache sands well. Prime it, seal it, then paint — unsealed mache drinks paint unevenly and blotches.
Where it fits today
Rigid-faced puppets, marionette heads, masks, and school or workshop settings where a class of twenty needs to build something for under twenty dollars total. It is the wrong choice for anything with a moving mouth.