Place colored modeling clay on sheets of wax paper and flatten the clay to a 1/2-inch uniform thickness with your hand.
Instruct the children to cut round shapes out of the clay with the open end of the empty clay containers.
Supervise the children stamping their thumbprints into the center of the clay cutouts. Help each child engrave his name into the clay above his thumbprint and the graduation date at the bottom of the medal with the pencil. Punch a hole through the top of each medal with a drinking straw. Set the medals aside to dry for 48 hours.
Cut 2-foot lengths of ribbon with a pair of scissors. Tie the ribbons to the holes in the top of the medals and hang the medals around the children’s necks at graduation.