What you need:
4 cups of flour
1 1/2 cups of salt
1 1/2 cups of water
What you do:
Mix the salt and flour in a bowl.
Add water gradually to form a ball.
Knead (pound, roll and pull) until it no longer falls apart.
Do your project and allow it to dry at room temperature for approximately 2 day (more for larger or thinker projects).
Store any unused clay in a sealed bag in the fridge. Allow it to warm to room temperature before you use it again.
I use this recipe for a ton of crafts. My favorite are seasonal decorations. You can roll it out and use a cookie cutter to cut out trees, bells or stars for Christmas, bunnies for Easter, hearts for a Valentine. Whatever you want. When the shape is dry, the children can paint them and use them for tree ornaments, necklaces, card decorations. You chose. Another option? Allow your child to create dinosaurs, animals, vehicles, handprints, anything they wish. Paint when dry.