Each group needs:

• 1 antacid tablet, such as Alka-Seltzer™ brand; do not use Tums™ brand; prepared by splitting in half and crushing one half-tablet into powder
• 1 film canister; film canisters are readily available at no charge from camera shops and stores where photographic film is processed, such as grocery stores, Target, Wal-mart and Costco; these businesses recycle the canisters and are often willing to donate them for educational use; most often, they have the solid black canisters (see Figure 1, center), which are good for this activity; the elliptical-shaped canisters used for Advantix® film also work for this activity (see Figure 1, left) 

• 1 stopwatch or a clock with a second hand
• small piece of construction paper, a strip of heavy tape (such as electrical tape), or a small cutout of dense foam
• Aqua-Thruster Worksheet, one per student

To share with the entire class:

• pin, to poke holes in the plastic film canister lids
• scissors
• blunt object such as a heavy textbook or brick
• safety glasses, enough pairs for the largest group
• large sink, tub or other plastic/glass container to hold water