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Active Time
20-30 minutes
Total Project Time
30-45 minutes
Key Concepts
Gears, mechanics


Did you know that gears are all around you? You can find them in wind-up toys, bicycles, carousels, cars and trucks, cranes, drills, wind turbines, analog watches, and so forth! If you've looked closely at a moving bicycle, you have seen gears at work. Are you curious about their purpose? In this activity you will use candy to make gears and explore why they are so versatile.


Sabine De Brabandere, PhD, Science Buddies
This activity is not appropriate for use as a science fair project. Good science fair projects have a stronger focus on controlling variables, taking accurate measurements, and analyzing data. To find a science fair project that is just right for you, browse our library of over 1,200 Science Fair Project Ideas or use the Topic Selection Wizard to get a personalized project recommendation.


  • At least two round plastic or cardboard lids of different sizes. Lids with diameters of about 5 centimeters and 12 cm work well.
  • Scissors or utility knife
  • At least 15 individual candies all of the same type, such as spice drops, candy corn or gumdrops
  • Large piece of scrap paper
  • Glue (a hot-glue gun works well)
  • At least two brads, one for each gear you like to make
  • Piece of cardboard or poster board, at least 20-by-30 cm
  • Permanent marker
  • Ruler
  • Adult helper
  • Optional: A lid with diameter of about 18 cm or more lids, they can be identical in size



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Active Time
20-30 minutes
Total Project Time
30-45 minutes
Key Concepts
Gears, mechanics
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