1 Sketch it

1. Draw Sam's heart where it belongs. Make it about the size of his fist.
2. Draw one artery in red, from the heart down to a foot.
3. Draw one vein in blue, from the foot back up to the heart.
4. Label the heart, the artery and the vein.

Word bank: heart, artery, vein, capillaries, lungs

2 Test it

1. Sit still. Find your pulse on your wrist with two fingers. Count the beats for 15 seconds.
2. Do 20 jumping jacks. Count again right away.

1 Sketch it

1. Draw the windpipe from Sam's throat down into his chest.
2. Draw two lungs, one on each side.
3. Draw the diaphragm as a dome under the lungs.
4. Label all three parts.

Word bank: windpipe, lungs, diaphragm, nose, air sacs

2 Test it

1. Sit still. Count your breaths for 30 seconds.
2. Do 20 jumping jacks. Count again right away.
3. Put a hand on your belly and breathe in slowly. Which way does your hand move?

1 Sketch it

1. Draw the path of one bite of food. Begin at the mouth.
2. Add the food tube, the stomach, the small intestine and the large intestine.
3. Number the stops from 1 to 5.
4. Label each stop.

Word bank: mouth, food tube, stomach, small intestine, large intestine

2 Test it

1. Measure 20 feet along the floor with a ruler or a tape measure. That is how long your small intestine is.
2. Walk it heel to toe and count your steps.
3. Put your hand just under your ribs on the left side. Your stomach is right there.

1 Sketch it

1. Draw the bones inside one of Sam's arms.
2. Draw the biceps on the front of the upper arm and the triceps on the back.
3. Circle one hinge joint. Put a star on one ball and socket joint.
4. Label the muscles and the joints.

Word bank: biceps, triceps, tendon, hinge, ball and socket

2 Test it

1. Test five of your own joints. Move each one slowly and gently.
2. Fill in the chart.

1 Sketch it

1. Draw Sam's brain inside his head.
2. Show the cerebrum, the cerebellum and the brain stem.
3. Draw the spinal cord running down his back.
4. Label all four parts.

Word bank: cerebrum, cerebellum, brain stem, spinal cord, nerves

2 Test it

1. Work with a partner. Your partner holds a ruler up by its top end.
2. Hold your finger and thumb open at the bottom end, ready to pinch.
3. Your partner lets go with no warning. Catch it! Write the number where you caught it.

1 Sketch it

1. Pick one thing you love to do, like kicking a ball, swimming or riding a bike.
2. Draw yourself doing it in the box.
3. Write what you picked on the line under the box.

2 Test it

1. All five systems are busy while you do it. Fill in the chart.