Set includes a full-color markable model of durable vinyl and an activity guide with background information, basic understandings, teacher-developed activities, a glossary, a key to model structures, color transparencies and a blackline master. The circulation process is reinforced with a colorful three-overlay transparency of the heart. A cutaway view of the interior of the heart can be seen and studied. Trace vessels throughout the body while viewing an enlarged cutaway section of a vein and an artery.