H2Oh! Classroom Demonstrations for Water Concepts provides a set of 45 classroom activities on water-focused engineering topics that are designed to enhance student learning. Each demonstration is short, so it can be performed as part of a lecture, and focused on visually presenting fundamental principles of water science and engineering. Demonstrations are grouped into five areas: fluid mechanics, hydraulics, surface water hydrology, groundwater hydrology, and water quality. Each demonstration identifies the targeted audience level, activity preparation time , duration of activity, learning objectives, materials, step-by-step instructions, and notes to assist the demonstrator. Some activities are accompanied by questions and answers. A final chapter provides additional resources for water resources education, including publications, web sites, equipment vendors and products, quick activities for fluid mechanics and hydrology, and music and videos with water themes. College-level instructors will want to integrate these activities into undergraduate courses in water engineering and geologic science. Some of the activities are also appropriate for younger students, making this a useful reference for middle and high school teachers.