Materials Needed:

For Engagement:
Ball and ring apparatus *
Burner or heat source
Goggles
* We suggest that middle school teachers obtain this apparatus from the high school physics teacher
OR
Ring stand
Small ring clamp
Glass bottle or beaker with a diameter slightly larger than that of the ring clamp
Alcohol or Bunsen burner

For the Exploration:
Per group:
2 rubber bands about 90 mm long and 3 mm wide (3 1/2 inch x 1/8 in)
Ring Stand
Ring clamp
Heat gun (a hair dryer may be used but the effect will be less dramatic)
Object with a mass of about 100 grams
Scissors
Goggles
Meter stick - optional

For the Explanation:
A rope long enough to extend across the classroom
Optional: a rubber band, ruler, and a freezer

For the Elaboration:
Per Student:
1 rubber band at least 90 mm long and 3 mm wide (3 1/2 inch x 1/8 in)