Have them take another piece of yarn, dip it into glue and place on construction paper in an interesting, but simple line. Let dry overnight. Children can then color inside spaces to make a design. Place bat in box. Pour tempera into small dish and add marbles.
Children use spoons to put marbles in the box.
Tilt box until the bat is streaked with paint. Mix purple, green, and orange by adding combinations of your primary colors in egg cartons. Paint a slightly wavy rainbow in each color across paper. Cut out the fish, and of course, the back is rainbow. I add a glitter table station, for those who want to jazz it up.