The National Aeronautics and Space Administration (NASA) has produced a distance learning series of four 60-minute video programs with an accompanying Web site and companion teacher guides. This teacher guide accompanies the fourth video in the series. The story lines of each program involve six ethnically diverse, inquisitive schoolchildren who meet in a treehouse. They seek the solution to a particular problem, and the NASA "Why?" Files series follows them through the steps of their investigation and final conclusion. In this program, the treehouse detectives have entered a plane contest. In their quest for information to build the winning plane, the students visit the National Air and Space Museum, a wind tunnel, an airline pilot, and an electronic classroom to connect with the NASA Dryden Flight Research Center. Students learn about the forces of flight, gravity, the history of flight, flight in animals, and various laws of physics. The teacher guide includes a program overview as well as geography, science, mathematics, and educational technology concepts as related to the National Standards. Each 15-minute program segment is described along with objectives, key vocabulary, suggestions for the most effective use of the videos and Web site in the classroom, and resources. In addition, each segment is accompanied by activities and worksheets. (PVD)