We used them for our high school science and math classes. They worked exactly as we wanted to poke holes in them so we could show how gases can build up and exert a force on an object in a liquid (water in this case). Fins were made from a small piece of duct tape and thick construction paper to help the "boats" move in a straight line, while the alka-seltzer reacted internally, creating a gas that propelled them forward.
π· Nikon 35mm f/1.8G AF-S DX Nikkor Lens - Black
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Fujifilm Instax Mini 11 Instant Camera - Sky Blue, Portable 4.8" x 4.2" x 2.6" Camera
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Video baby monitor Kodak CHERISH C225, black
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πΈ Fujifilm Instax Mini Instant Film (5 Packs, 100 Sheets) with 10 Plastic Desk Frames, 20 Paper Frames, and 60 Sticker Frames
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