Each group needs:

• 1 empty, wide-mouth jar
• 1 sheet of Mylar or a helium-quality balloon (the same material used for aluminized party balloons; Mylar is relatively impermeable to gas)
• 1 heavy, thick rubber band
• 1 small ball of poster putty (or chewing gum or other adhesive)
• 1 toothpick (or 6-inch piece of dry spaghetti noodle or broom straw)
• 1 piece of cardboard, ~8 x 10 inches, for the barometer scale
• The day's barometric pressure, from newspaper weather page, television or radio weather broadcast, or weather website
• Barometric Pressure Log, one per student
• (optional) graph paper (only needed if students are graphing data), one sheet per student