Get Pass cones, make a basket, get your own rebound, pass defender, pass to Feeder once half court, Feeder passes to next in line, and continue rotating. After the first 3 round a defender starts guarding the basket as well.
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.