I coach a 8U coach pitch team as well and have coached all of my son's baseball teams since he was four. I could write a book on my learnings over the past four years. In my opinion, the keys to success, success being keeping the kids interested as much as possible and keeping the parents as happy as possible, are keeping the kids interested as much as possible and keeping the parents as happy as possible. If the kids aren't interested, then you will never get them to learn anything. If the parents aren't happy, then they can be a pain in the ass and even more importantly, if they are happy then they're more likely to be somewhat committed, which usually rubs off on the kids.
The best way to keep the kids interested is organized, fun practices with as little of standing around as possible. Idle hands, yada yada. Split the kids up as much as you can into smaller groups utilizing station work to focus on certain areas. Have a plan going in to practice, what drills to run, what stations to set up and how much time to spend on each one. I can get into the specifics of the drills and stations if you would like? I can talk all day about this stuff.
As far as technique and how much to try to teach them, well that's an inexact science for sure. I just focus on the fundamentals and just feel my way through the reactions from the kids on whether to give more or pull back. I will say the little shits are like sponges and I'm always shocked how much they learn and retain.
With the parents, clear, concise and timely communication is imperative. Meet with the parents before your first practice and set the expectations for you as a manager and the season as a whole.
I've got a run, but let me know if this is helpful. I know it's kind of high level, but I can go to the details if you're interested. Feel free to PM me as well.
Also, here's a website that has decent info on dealing with parents and practice structure. (
LINK)