Bobby and Carmen are at summer engineering camp. They have been challenged to design and build a useful project for their fellow campers. Time is short and most of the materials have been used! Will Bobby and Carmen succeed in using science and engineering to build something useful before their afternoon hike? Readers will engage in identifying, describing, classifying, and measuring objects by their physical properties, such as flexibility, texture, and dimensions. The interactive nature of this ebook allows students to learn that physical properties can be observable and measurable. While learning about physical properties, students will join Bobby and Carmen in using engineering design process steps to solve the problem. In Properties Matter, Bobby and Carmen learn from their setbacks as they redesign, rebuild, and make improvements to their project. They persevere through the design steps and find success and feel pride at the building of their project.