This poster is a read, show, and share tool. It is physically central to the "unfolding" concepts of its teaching unit. It presents three main themes: A light on the past, A light on the present, and A light on the future—covering 150 years, and introducing exciting electrotechnologies for the future. Its reverse supplies background information and suggestions for student learning activities. Grades 4-12, 23" x 35", Full Color front and back.