Fifth graders in Mrs. Caldwell's class would soon experience a "change" as they made the transition from elementary to middle school. Participation in classroom inquiry investigations and schoolwide science enrichment events had already developed students' enthusiasm for science; here was an opportunity to solidify that enthusiasm. Guest science teachers--two preservice elementary teachers and their instructor from a local university--would teach a science lesson on phase changes to communicate to these soon-to-be middle school students the message that "science is cool." Additionally, understanding phase changes (especially water) is an important concept for understanding weather phenomenon. (Contains 1 figure and 3 online resources.)