Our preschool is set up so that each day small groups of kids from my class go across the hall to science. During some units, the science curriculum corresponds with what we are doing in my class and other times they are learning about something completely different. During our school-wide literature unit (when I did Fairy Tales), the science teachers did a wonderful Eric Carle unit. The children learned about the different animals in Carle's books and then created cool 3-D animals and beautiful backgrounds.
The body of the firefly is a pinecone that was dipped in glue and then glitter. The head is a pom pom with goggly eyes and the wings are cut from the paper the kids painted. The pictures really don't do them justice...they are so cute.