How about getting your kid to create a galaxy during his science class the inexpensive way? See what I found in enchanted learning.
Materials: Fine sand (or glitters), glue, black paper, old news papers
1. On a black paper, draw a rough sketch of our galaxy, the Milky Way using a pencil (or white crayon). Our galaxy is a spiral galaxy with five arms. The center is a dense disk containing many older stars.
2. Apply glue onto the lines. Sprinkle the sand onto the glue.
3. Tilt the paper and shake off loose sand (glitter).
* Optional: label the arms of the Milky Way and label where our Solar System is located.