Sorry I'm a month behind.
I've coached 9/10s the last two years and going on my 3rd year (no kids, just love coaching).
Dave Cisar at
Youth Football Plays and Playbook is an excellent source. I run similar things to what he does and use his materials as a guide. Our league prevents us from doing a few things he does, but overall he presents things very well.
QB footwork, play, and throwing can be tricky at this age. Honestly, I prefer not do deal with it. While they're certainly important as they grow older, I found that trying to teach some of those concepts to a 9 or 10 year old gets the kid thinking about a lot of stuff outside of just playing football. Cisar eliminates the position by using single wing football.
My first year at this level I ran double wing and pro set formations. Double wing was QB footwork intensive. Seeing as we can only practice two/three times a week, I began moving more to the pro set.
If you're dead serious about coaching quarterbacks past this age, you might consider Darin Slack's videos for quarterback play. Some great stuff there, but a lot of his material would be over the head of 9/10s. But, if you're looking to drill in concepts of footwork and arm motion, that's the source without a doubt.