Two-year-old Ben and his father invent challenging ways to get a billiard ball into the pool table pocket. Ben uses the cue sticks to channel the ball into the pocket. Ben’s father offers hints now and then, and his uncle offers ways to make the game more complex. Marvel at Ben’s flexible thinking and adaptive changes in the rules. Observe Ben figure out what to do when the ball rolls backward. His natural desire to explore and invent becomes the catalyst for rich problem solving and learning about incline, speed, angle, and direction. Ben’s experience shows us how open-ended play fosters high-level thinking.