Let the kids use white crayons to draw large stars on to black construction paper, and help each child cut one out. Pass out paintbrushes so children can spread a thin layer of glue across their stars, then sprinkle on salt or silver glitter. When the glue dries, shake off extra glitter and hang the stars from the ceiling. Ask children to guess what makes real stars sparkle.
You don't need to wait for sundown to take preschoolers stargazing. Create your own universe on the classroom ceiling using glow-in-the-dark stars. Arrange some of the stars into the shapes of real constellations, such as the Big Dipper. Cover the ceiling with stars, then cover windows with dark fabric and turn off the lights. Invite children to lie down on their backs. Use a laser pointer or dim flashlight to point out the constellations. Encourage children to look at the night sky later on to spot these sights.
Explain what is meant by the word "universe," then demonstrate to preschoolers how the universe is constantly expanding. Blow up a balloon halfway and let children cover it with star stickers. Blow the balloon up the rest of the way and tie it off and ask children to make observations about what happened to the stars. They should be able to see that they moved further apart from one another. Explain that this really happens to the stars in the sky, although too slowly for us to be able to tell.
A visit to your local planetarium can open children's eyes to all the wonder of the stars in the sky. If you can't make it into the planetarium, invite an employee to come and present a slide show to the class. In towns that don't have planetariums, borrow a children's planetarium DVD from the library to show to children. Having experts speak to children will teach them that there's an entire field of study devoted to the stars, and can help pique their curiosity about science and outer space