This Science and Children article includes background information for the teacher and three investigations to share with the students. First, students create waves using a jump rope, then water, and then they model the movement of molecules using marbles and a book. Through these activities, students will develop an understanding of how energy moves through all types of waves, and they will model the process of energy transfer. The activities use simple materials, but are effective at demonstrating wave energy. The instructional guide suggests questions (with answers) that may be used to guide student learning.