Set 3 blocks (white board eraser) out in a straight line about 10 feet apart.
The player will do a defensive slide and pick up the block with the closest hand. Once it has been picked up it will be switched to the other hand.
When the player gets to the next block they will pick up with the closest hand and drop the 1st block they picked up.
The drill will continue until the player gets back to the original spot.
Good team defence is five players guarding the ball, not five separate one-on-ones. The shell drill is where that starts, so here is how to teach help-side positioning and rotations from the first week of the season.
Rebounding is the least glamorous thing in basketball and one of the most decisive. It is also almost entirely a habit, which means it is entirely coachable.
Good spacing is only the start. The best modern offences teach players to attack the defence's rotations and play in a permanent 4-on-3 - here is how to coach that read.