Have you heard of Brave Writer? It was formed by Julie Bogart who homeschool 3 (or maybe 4) children all the way through. One had dyslexia and another had ADHD. She has online courses, a subscription based system that send you assignments, and a book/curriculum you can pull from. She also does a lot of periscopes and youtube videos with that have a lot of really helpful information. She has a great system for reluctant writers and builds on the relationship between the parent and child through writing. It is beautiful. I highly recommend checking out her site.
http://www.bravewriter.com