Assuming you will have 20 kids in total, you can divide them in teams of 5 and assign them to one basket/half court per team (If the numbers vary just modify the numbers so that teams are as even as possible)
If the kids are not too unfamiliar with ball sports, and if you have the possibility put some cones in triangular path like: // in one lane, or two lanes parallel to one another. Instruct the kids to dribble following the path you have designed and pass to a teammate on particular occasions (for instance when their running paths come close to one another), and as they come close enough to the basket the player with the ball attempts a shot/layup, where the one who passed the ball last is responsible for getting the rebound and passing the ball back to the other teammates waiting to start their drill.
If kids are too unfamiliar with basketball or don't really get what they are supposed to do, you can change the rules accordingly to make it suit the group. One alternative is to make teams interact with one another and create some competition feeling, for instance if the player who's taking the shot misses, the other team gets the chance to take the rebound and "score a conversion".
After a certain amount of time passes, you can blend the teams, or get the teams who won their respective "matches" meet one another.
I am fully aware that what I suggest is more of a real training drill than a playground game, but hey if you manage to spark a passion for sports in the kids it's only for the better, right? :)