While I don't know of a specific source for state history curriculum materials, please allow me to offer a slightly different suggestion. When I covered state history with each of my students, we did it in conjunction with Sonlight History/Bible/Literature packages D and E. I found it was very helpful to integrate our state history studies into a study of American History as a whole. It allowed my children to see how our state's history played a part in the history of our country as a whole, instead of looking at it as an isolated series of events. I utilized my local library to find a couple of resources that provided me with a chronological timeline of my state's history. Then I plugged in field trips, videos, and other library materials as they fit within the timeline of History/Bible/Literature packages D and E. We enjoyed a wonderful couple of years studying both American History and our state history.