Our five-day unit focuses on sound waves and their properties, and took place in a first grade classroom at McManus Elementary School. The students were asked to collaborate with a partner and create a telephone to communicate with using the materials provided. Students created building plans, selected materials, and redesigned their creations if they could not hear their partner through their phone. We explored sound properties including vibration and how sound travels by watching videos, reading books, and exploring with tuning forks. Students focused on two core ideas: sound makes things vibrate, and vibrations can cause sounds; and sound can travel through objects. One of our main goals was for students to create a device that allows them to communicate sound. Our second unit goal was for students to develop the understanding that sound makes things vibrate and vibrations can cause sounds. Another goal was for students to explore different types of sound, and learn that sound can move through objects.