In various conversations I've had over the last few years, I've noticed that everything seems to come down to definitions. How you think of something makes the difference as to how you work with it. So, I thought I'd lay out some of my definitions of the types of schools in an attempt to help clarify things.
2 - Virtual School (or schooling from home) - In this case, the parent becomes a helper to the teacher, but isn't the primary teacher themselves. The school involved (for example, Georgia Cyber Academy or Georgia Connections Academy) provides materials and teachers for the students. They will follow all state regulations for requirements for materials to be learned. You will follow all state requirements for testing as well. The advantage here is that the student stays home. This is an excellent way for medically fragile kids to be able to get their schooling without having to attend. It's wonderful for families that are involved in their student's education but who do not want the responsibility of the primary curriculum. In many cases, the families will supplement with additional material (religious or otherwise) and field trips.
3 - Brick & Mortar (B&M) school - Your traditional state/county schools. Students ride a bus (maybe) to school, are taught at school by teachers, then return home at the end of the day.
4 - Hybrid school - (example - Gwinnett Online Campus)
This is one that combines your virtual school with your brick and mortar. Majority of the learning is online via the computer. The student will go in to a fixed location on some form of schedule for additional teaching or labs with teachers. It must still follow all requirements as given by the state, but has many of the advantages (and disadvantages) of each of its parents.