For a new coach - this is what I did.
Defense -
Teach one zone defense and one press defense - either half-court, or full court - depending on rules and athletes.
Work on rebound a lot, then work on it some more.
Offense
One zone offense - we generally used a triangle on one side of the floor and not a lot of screening, because screening a zone - which most teams will play - only helps you get perimeter shots really. Just too congested for any meaningful post screens, in my experience.
One baseline inbounds play - we ran line. Get all four kids to line up facing inbound passer - generally point guard. On break first guy goes to opposite block second guy to same side wing, third guy ball-side block and last guy to ball. Passer has options, but teach them patience as last guy is always open for short jump shot.
I had a lot of good drills - really worked on pivot foot, reverse pivot, etc... Have three people in the drill, as many trios as possible depending on numbers on team.
Line up across the lane facing each other - one step wider than the lane. Have two passers, one defender and it is basically keep away - except they can't dribble or throw over the player. All passes must be shoulder level and below. If the defender deflects the pass, they swap positions with the passer. Great for teaching many aspects, but I used it for pivot foot, reverse pivots - rip throughs on offense, starting low and bringing the ball high - sort like Kevin Durant.
Also did a lot of shell working, showing defenders where to be when the ball is moved around the perimeter - teaching jumping to the ball and moving while the ball is in flight. If you are on two passes away both feet are in the lane, if you are three passes away, body is under the basket. Really focusing on defensive movement and feet positioning - open toward the ball, not away from the ball.
1 v 1 and 2 v 2 drill
Everyone stands on baseline. I select two players to go against each other - start underneath the corners of the backboard. I roll the ball to the center of the court and they chase it. First one to arrive is on offense, second on defense. If you score you get two points, if you stop them you get one. I team them up to 2 v 2 and even 3 v 3. Great for competiveness.
Also did a lot of shooting games - one shooter one rebounder, different spots on the floor - first team to 10 from any given location - switch after five shots.
Full speed layups - every practice!
Anything to make it competitive.
I never ran sprints in practice, I just made them run in almost every drill, so conditioning occurred with practice.