Hi Natalie,
I started teaching guitar a few years ago, and the best place I ever went was the Teaching Guitar Workshops. They are a week long (Monday-Friday 9-5) and happen several places throughout the summer. Unfortunately I think this year they might not be too close, but you may be able to find something that works. The workshops are sponsored by GAMA and you get a ton of free books and materials, and you also get a free guitar! The clinicians are all extremely qualified and many have advanced degrees in guitar pedagogy. Great for Elementary through High School.
Here’s the website! http://www.guitaredunet.org
I’d also be happy to share anything I have to help you in this process. Let me know!
GOOD LUCK!