Hey Mark,
Congrats on getting your own team to coach. I still remember the first time I was called "coach" out on the ice...it really puts things into perspective doesn't it?
What I've noticed with kids that age is that you really have to do things that keep their attention. Engage them. Try to keep the drills fun while teaching them at the same time. Are you looking for goalie-specific drills or drills for the whole team?
It already sounds like you're on the right track. You mentioned that one of the goalies is good and may have good deal of potential. What was it that made you think that? Analyze thier skills and prepare accordingly. You may even want to take some time and work 1 on 1 with him/her to do some unique drills or impart unique knowledge that a more advanced goalie would find helpful.
Basicallly, work to make the position personal. Goalies are special. Treat them that way. And make sure they know it too. I always make time to have at least one "goalie specific" practice per week and at the end of practices I have my goalies stand by the doors and have the team line up and tap them on the pads on their way off the ice. I also talk to parents to let them know how their little goalies are progressing. That can help seed confidence in young goalies and may actually make them want to come to practice and pay attention to what you have to say. Also, parents will love the fact that you are taking personal intrest in their child. Its really amazing to watch the development of young goalies who are hooked on the position!
In terms of how you approach your coaching, try to approach it the same manner as you would your own game. Think about the things that make you a good goalie - your skill sets, your idiology, your experiences (there is nothing like teaching to really illustrate what you know) and incoporate them into you lessons. You'll develop your own style, it just takes a little time. I've always perscribed to the "This is what worked for me, maybe you should try it" mindset.
Are you looking for goalie specific drills or drills for the entire team?
I hope you found some of this helpful. Let me know if I can be of any assistance.
Oh, and on a personal note I think its awesome that you've come on here asking for ways to be a better coach. You really seem to care about what you are doing. That, in and of itself, is going to make you a good coach!
Good luck out there!
-Tim