Be Prepared: A mailing tube of eight inches in diameter and 36 inches in length works well for this activity. Set up an attractive arrangement with a pail or container of the balls and the tube. Make sure the balls can easily roll through the tube. Place one end of the tube on the block or small box so the tube angles downward. Put supports on the sides of the tube resting on the box so it stays in place. Put the second (empty) pail near the lower end of the tube.

Be Prepared: Secure identical mailing tubes. Tubes of eight inches in diameter and 36 inches in length work well for this activity. Put one of the tubes flat on the floor. Place the balls in the pail and put the pail near one end of a tube. Put the second tube and block (or box) nearby.

This activity option is designed to help a toddler explore how the angle of a tube is connected to whether and how fast a ball rolls through a tube. Your approach to the activity will depend on the toddler’s experiences with rolling balls, especially rolling balls through a tube (as in Option 1). Possibilities for supporting the toddler’s experiences in this activity are described below, listed from simpler to more complex arrangements. Use one or more of the possibilities in response to the toddler’s engagement in the activity. Consistently use gestures to complement your words.

Open the session by displaying and naming the tube, and encouraging the toddler to look into the tube. You may wish to move your hand or fingers on the opposite end of the tube to strengthen the toddler’s understanding that the tube is open at both ends. You also may wish to help the toddler stand the tube on one of its ends so it is straight up (vertical position) and drop a ball through the top of the tube to demonstrate the tube is open.

After a period of exploring the tube, offer one or more of the following arrangements:

• Put the tube flat on the floor and gently push a ball into the tube. Use a light push so the ball does not roll out the other end of the tube. Explain that the ball is inside the tube. Suggest that the toddler lift one end of the tube. Draw attention to how the ball rolled out at the other end. Explain what happened. Repeat by gently pushing the ball into the tube. Again, encourage the toddler to lift one end of the tube to see what happens.
• Raise one end of the tube using a block or box. You may need to loosely tape the tube to the box or block to keep it steady. Invite the toddler to put one or more balls through the tube. Describe what happens. (This is a repeat of Option 1.) Then help the toddler add 3–4 small blocks to raise the end of the tube even higher. The toddler may notice how the ball rolls faster when the end of the tube is higher. Invite the toddler to participate in both actions: putting balls inside the tube and catching balls as they roll out of the tube.
• Place two tubes side by side, each with one end raised using a block or box. Then help the toddler add 3–4 small blocks to raise the end of one of the tubes higher than the other. Draw attention to how the end of one tube is higher than the end of the other tube. Invite the toddler to put one ball in each tube at the same time (or the toddler puts a ball in one tube and you put a ball in the other tube at the same time). Ask which ball rolls faster (comes out sooner). Repeat the rolling of balls in the two tubes at the same time.