These two mentions... TEACHER NOTES Teachers! Did you use this instructable in your classroom? ... The racquetball that my son was launching in the videos ab

These two mentions... TEACHER NOTES Teachers! Did you use this instructable in your classroom? ... The racquetball that my son was launching in the videos above was partially filled with water to bring it up to a regulation weight of 3 ounces. Water-filled racquetballs make fun projectiles. I had wood shop in middle school. Imagine a shops teacher assigning this as a final project to his 8th grade students.