DESCRIPTION Here is a great pair of coloring sheets to teach the flow of oxygen and carbon dioxide in our bodies. The first page shows a simplistic view of the human circulatory system. Students can see major organs such as lungs, liver, stomach, and intestines. Students will color the blood flowing AWAY from the heart and lungs RED. This is because the blood flowing away from the lungs has just been oxygenated. Typically, human body books color oxygenated blood red, so this matches what student