This unit is aligned to multiple Performance Expectations from the following topic arrangements: 4-PS4: Waves and Their Applications in Technologies for Information Transfer, and 4-LS1: From Molecules to Organisms: Structures and Processes. Students will first investigate the physics of sound, then use their observational and data analysis skills to understand the multiple applications of sound in comparing different frog calls. This review will primarily focus on lessons that address Performance Expectation 4-PS4-1: Develop a model of waves to describe patterns in terms of amplitude and wavelength and that waves can cause objects to move.