In this video, musician Jake Shimabukuro uses the pitch of musical notes and vibrations in hertz to illustrate the concept of ratios. This clip is from Center for Asian American Media. In the accompanying classroom activity, students watch a portion of the video in which Shimabukuro explains the 3/4 time signature. After a brief introduction to musical pitch, students watch the rest of the video. They then use a chart listing the frequency of musical notes to identify ratios among notes that are one or more octaves apart. To get the most from the activity, students should have some familiarity with physics of sound.