Scrimmage as much as possible
Youth hockey is supposed to be fun. Do you think it is more fun to scrimmage, or skate the circles and do wind sprints all practice? When I was young I never played organized hockey, it was just a bunch of kids playing the game on a pond. We played for hours and hours and I loved it. I never did a drill in my life until I was on an organized team as a senior in High School. Yet, I was still able to play four years of college hockey.
Wayne Gretzky played hockey for hours in his back yard. The key word here is "played". He didn't "skate the circles" - he played, and played, and played. Kids develop great moves when they can play and experiment. Wayne believes that North American hockey players are becoming "robots" because they always play organized hockey, with a coach yelling at them if they try any fancy moves. And I agree.
I'm not suggesting that every practice become a scrimmage, or that we eliminate all drills. Over the course of a season I probably spend 50% of the practice time in drills, and 50% in scrimmages. 60-40 one way or the other is fine too. But I've seen coaches that are 99% drills, and seem to take pride in "never scrimmaging". Yet these same coaches say, "hockey should be fun". A great part of the fun is playing, not just skating the circles backwards, without a puck.
Playing a lot is particularly important for young kids so they develop a love of the game early. However, the prevailing philosophy I run into seems to be "don't let the little kids play until they learn all the skills". This is absolutely wrong. They learn the skills by playing, or at least Wayne Gretzky did, and he was a pretty good.
I frequently arrange extra ice time for the kids. These extra sessions are always pure scrimmage. I believe if a kid is going to show up for extra ice, he should be rewarded by playing. And these scrimmages are "free form". The kids are encouraged to try moves, play a different position. I play with the kids, not coach them. Parents come out and play. It is really "pond hockey" on an indoor rink. We have a wonderful time. And, all the kids show up. In fact, kids from other teams show up! The kids always ask me, "Coach, when can we get some more ice and do this again".
When I coach little kids (Mini-mites, mites), we would scrimmage without rules. No offside, or icing. Just let them play. They love playing. I worry about teaching the rules during regular practices.
Hockey should be fun, and it is fun, if you let the kids play. We have over-organized kids to death.