Washington Online, which is now Utah Online School, is wonderful. They provide free, flexible curriculum and offer support without being overbearing. I have a daughter in 6th grade, a son in 3rd grade, and a daughter using their preschool program. This is our second year with them. Before this, I home schooled and we tried public school. This is the best mix. We have the freedom and flexibility of home, but the added support of a school with lots of field trips and teacher input when we ask for it. We don't have to provide samples of work or keep track of hours. We just show progress and keep up with online assessments. They have clubs and incentives available. They are a great school.
Washington Online uses the K12 program. They are wonderful to work with. The principal is amazing. Their test scores aren't great (in case you look those up) but that's because there are several special needs kids involved and it's all based on parent teaching since it's online and at home.