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Great white sharks are terrifying, but also awesome. They’re huge, their teeth are as sharp as knives, and some even have a taste for human flesh.

But as frightening as great white sharks may be, their ancestor, the megalodon, was even scarier. In this lesson, students model the bodies of different sharks using cylinders, and explore how the volume of a cylinder changes when its dimensions change. They learn that the megalodon was a massive ocean beast, but after estimating the dietary needs of such a large animal, they discover that its size may ultimately have led to its downfall.

Students will

  • Use cylinders (and optionally, cones) to model the shape of a great white shark and a megalodon
  • Apply the volume formulas for cylinders (and optionally, cones) to estimate the volume of different sharks
  • Explore how the volume of a cylinder (or cone) changes as the radius/height change
  • Estimate how much food the megalodon would have needed to eat in order to stay alive
  • Apply arguments about megalodon’s dietary needs to discuss possible reasons for the megalodon’s extinction

Before you begin

Students should know what cylinders are, and be able to evaluate the volume formulas for cylinders given their radii and heights (for example, if a cylinder has a radius of 2 and a height of 3, they should be able to evaluate the formula V = πr2h at h = 3 and r = 2). The modeling students do can also incorporate volumes of cones, though this is not required. Finally, it’s best if students don’t have a crippling fear of sharks.

Common Core Standards

Content Standards
Mathematical Practices


Discovery Channel's Shark Week, National Geographic, Stephen Godfrey