Cut a paper plate in half and attach crepe-paper streamers in the colors of the rainbow along the straight edge. Attach the streamers by punching holes in the plate, then threading the streamers through the holes and tying them. The crepe paper also can be taped or stapled. Explain the order of colors in the rainbow to the children using an illustration so they can see what you are talking about. When finished, the preschoolers can run with the paper-plate kites and they will be trailed by a colorful rainbow.
Draw an arch shape on white construction paper. Divide the arch into seven sections. Have the children to fill in the sections with rainbow colors. You can use a variety of materials to fill in the rainbow: pieces of construction paper, tissue paper, colored dried rice or pasta, pieces of yarn or scraps of colored fabric. Glue the materials in place to make the rainbow mosaic.
Fingerpainting with pudding is safe activity for young preschoolers or toddlers. Make instant vanilla pudding according to package directions. Divide the pudding into seven small bowls and use drops of food coloring to make rainbow colors. Give each child a sheet of waxed or freezer paper and drop a dollop of colored pudding for each stripe of the rainbow onto the paper. The children can paint the rainbow with their fingers.
Cut a strip of paper about 2 to 3 inches wide and long enough to fit around the child's head. Invite the children to decorate the paper with rainbow stickers or rainbows drawn with crayons. Fasten the ends together to make a headband. Attach crepe paper streamers in rainbow colors with tape or staples along the back half of the headband. Place tape over the staples to prevent scratches or hair pulling. Let the children wear the headband, and the rainbow streamers will flutter behind them as they walk or run.
Put a small amount of milk in seven cups. Add a few drops of food coloring to each cup to make rainbow colors. Using clean paintbrushes, let the children paint pictures on a slice of white bread. Make sure they do not saturate the bread with too much milk paint. Toast lightly for a slice of rainbow toast.