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Sports fans are familiar with slow-motion instant replays. Fans of nature shows have seen a flower bloom in a matter of seconds. But how, exactly, do people create videos that slow time down or speed it up?

In this lesson, students use unit rates to explore the frame rate of a camera and video player. They discover that filming at a high frame can be used to create a slow motion effect, while filming at a low frame rate can make motion look sped up. In the end, students have a clear idea of how these tricks work, and will be able to create stunning videos on their own!

Students will

  • Understand frame rate as a rate, and calculate how much time passes between frames given a frame rate
  • Discuss the relationship between frame rate of a video and its quality (i.e. how smooth the motion will look)
  • Calculate how long it will take to play a video using the frame rates for the recording and playback devices
  • Determine how different frame rates can be used to create slow-motion and time lapse videos

Before you begin

Students should be able to fluently multiply and divide whole numbers and decimals. This lesson serves as a nice application of unit rates for students with little prior experience.

Common Core Standards

Content Standards
Mathematical Practices


GoPro, filmmakers everywhere