Again, with youngsters, do about 90 minutes. You can have both girls and boys doing this clinic. In the clinic setting, you should teach individual player skills... save team concepts, offensive sets, plays, zones, etc for their team coaches. You need to teach them correct fundamentals and still make it fun for them. See Saturday Morning Youth Camp.
Recruit several assistants. We like to involve some of our high school players (boys and girls). It's good for them to "give back" and they generally enjoy helping the younger kids. The kids consider them their "heroes", so it works both ways. In demonstrating our drills, we have our player assistants demonstrate... I would totally lose any credibility that I might have if I still tried to do them! Sad but true... it's heck to get old!
Spend about 10-15 minutes on stationary ball-handling and dribbling drills. Get them all in one big circle, spread out, with the instructor in the center of the circle. Each player has a ball. The instructor goes through the ball-handling drills and dribbling drills and the players follow his example, doing the same drill the instructor is doing.
Since I am getting older and am not as skilled as I was years ago, I have one of our excellent high school players do the ball-handling and dribbling demonstrations... they are heroes to the kids! Have a couple coaches walk around the circle helping kids who are having difficulty.
We teach the triple threat position (so you are in a position to either pass, shoot or dribble) during our stationary dribbling drills... while they are dribbling, yell out "triple threat!", and then everyone suddenly stops the dribble and gets into triple-threat position.
Then, spend five minutes on sideline dribbling drills.
A quick trip to the drinking fountain... then full-court dribble moves drill.
Play a couple quick games of dribble tag.
Do 5-10 minutes of two-man passing drills... use the "Simple Partner Passing and Catching Drill", for the chest pass, bounce pass and overhead pass. Demonstrate correct technique... step into the pass, hands on both sides of the ball, snap the pass finishing with the thumbs pointing down.
Work on lay-ups, demonstrating correct footwork. Split them into two groups (equal talent) with a group on each basket. Each group makes two lines (shooters and rebounders) along the sidelines. Start with right-handed lay-ups.When you say "go" each group starts doing lay-ups, with the shooters going to the end of the rebounding line and the rebounders going to the end of the shooting line. Every time a lay-up is made, that group yells the count (the number they have made). First team to 10 wins... the losers have to do five push-ups and the winners get to count for them.
You can have similar competitions shooting short shots in the paint area. First, demonstrate correct shooting technique... the "platform", "L", "hinge", "gooseneck". Realize of course that correct shooting form is difficult for very young kids who lack the strength to shoot with one hand... but at least show it to them, and encourage them to try, not worrying about immediate results.
Here's a drill variation the kids love... now they are all on the same team. Have a shooting line starting in the center of the free throw line area, and a rebounding line near the basket. The rebounder will pass it to the first person in the shooting line, who steps in to about the hash marks (depends on the age) and shoots.
The kids yell out their number of baskets each time one is made. You give them a time limit and a goal of how many shots they must make in that time period (adjust this based on their skill level and so every player gets to shoot at least twice). If you have a big group, you may want to run this on each end of the floor. Make it challenging for them.
If they fail to make the goal in the allotted time, they all have to do five push-ups. Now here's the part they love... if they succeed in "beating the clock", then the coaches all have to do five push-ups! They love counting for you when you are down doing your push-ups.
Use your imagination... you can create other little games for them.

Spend the last 15-20 minutes scrimmaging... man-to-man defense, no full-court pressing. Divide the talent equally and don't have the same kids on the same team each week... mix them up. When you have both girls and boys, I have found that it is best to split them up and have the girls scrimmage on one end (use the side baskets) and the boys on the other. When playing together, some boys will never pass to the girls and the girls get upset and frustrated. So if you have enough players, let the girls have their own game.
At the end of practice, get them all in the huddle and tell them how well they are doing, and advise them to do dribbling and ball-handling every day at home for ten minutes. Then everybody puts there hands together and yells your school mascot name-- like "Rayders!!!"