Lesson Summary Students investigate how spheres roll down different arrangements of grooved track (runway).  In the last part of this lesson, students work as a whole group to make a runway for a sphere to travel along without stopping. Teacher Background During this lesson, students discover that spheres roll in all directions because all parts of a sphere are round.  Students will also discover that it is essential for a runway to start high and end low to enable the sphere to travel the full length of the runway. Set-up/Management Tips You will need two or more 45 minutes sessions to teach this lesson. The breaking point for this lesson is just before the long runway challenge. If student groups ask to put their runways together encourage this, it will begin to prepare them for the big runway challenge. When attaching and detaching the runways be extra careful with the tape.  The runways can tear easily. There is an assessment sheet you may give students at the end of this lesson, Marble Runways.  This assessment looks at whether students understand the importance of having runways start high and end low. Be sure to copy the Marble Runways sheet prior to the lesson.  It can be found in the manual under Investigation Duplication Masters. Before class have chart paper ready for recording content chart items. Literacy Support Books Available Through VAST Mediagraphies: There are currently no VAST Mediagraphies listed for this unit.  Science Stories There are no Science Stories with this lesson. Scientific Vocabulary The following words are key vocabulary words that will be introduced in this lesson and reinforced throughout the unit: Sphere Runway Loop Spiral