In this activity (page 1 of the PDF), learners will stand twelve feet apart swinging a rope at the slowest tempo possible while someone uses a stopwatch to record the number of twirls per minute. Based on this frequency, learners will predict whether the tempo will speed up or slow down when the twirlers move closer to each other. Use this activity to introduce the terms frequency and period. Relates to the linked video, DragonflyTV: Double Dutch.