Piece together this cross-cut of our tickers-arteries, aortas, and all. Grab the atria and ventricles that team up to pump nutrients throughout our bodies. Spot the arteries that transport blood to the lungs and the veins that whisk away waste products. Click the valves together that keep our blood circulating in the proper direction. Arrange the special myocardium muscle that squeezes the heart into its beat. When finished, kids can lean back and appreciate their hidden anatomy, larger than life.