The Shell Drill is great for demonstrating proper man-to-man defensive positioning as the ball moves around the court. But in my experience, if it’s used too much, it winds up reinforcing bad habits. Because they don’t need to worry about the offensive players moving, defenders start to ball-watch and they begin to settle into flat-footed stances on and off the ball. At Calhoun, after we’ve used the Shell Drill for several practices, we use the “3 Stops” Drill in which each team is trying to be the first to get 3 consecutive stops. But here’s the catch: a team can’t earn a “stop” unless it performs every Shell Drill principle correctly in the live-play situation.
