I can't answer for the regulatory questions, but I can tell you on time spent on academics... We unschool here in South Africa.
My kids set quarterly interests and goals for learning and then we break that down into weekly and then daily goals. We write a daily list for them to monitor and tick off. ANYTHING can go on the list - I am quite confident that when they choose to do it, they will learn something and I can spin it into a subject if I ever need to do so.
So things like "LEGO", "rollerblading", "climb big tree", "make a cake" will be on the list as well as things like "do 3 pages/20 minutes of "x" maths book", "work on 3D model", "set up science experiment", "practice violin", "German language lesson" etc.
When they choose to do a course or class, then I explain that this comes with certain obligations like attending the classes, completing assignments etc. Music indicates daily practice per instrument. So does a particular maths program they are all currently involved in. So those are givens in their day.
If I have to add it all up together, the official "working" time takes us no more than 45 - 60 minutes a day on official learning stuff. (Aiden is 7 and is currently working around grades 3 - 5 level and reads at about grade 5-7 levels, Nathan is 5 and currently works around grade 3 level and reads around grades 4 - 6). I don't count the things they then add to their list later; this is additional science (snap circuits, experiments, basic kitchen chemistry, online videos), baking, gardening, projects, outings etc.
Often we do a bit of something then take a break then do a bit of something else and then another break. This works well for the younger ones (I also have a 3 year old) and for me to do my work (I run my own business). I find that the shorter intense work sessions work well for helping them be self-directed and to teach them to work on their own or together.
We spend two full days per week with a group of unschooled kids and on those days they work and play hard as a group - their lists are a lot shorter and they go with the flow of the kids they choose to hang with for the day.
For us, unschooling works - suddenly a 1 month road trip becomes learning and has fueled interest and passion for so many new learning adventures! It means that if none of us feel like it, we can rather pack a picnic and go to a museum, a park, the zoo - and we all still feel it was a productive day.
I love this model, and I love that it means we can go as slow, as fast, as long, as late as we need to. It means that an astronomy class at 8pm is okay, as is sleeping in the next morning and then relaxing with a book under a tree before a swim.
I get the feeling that this is how childhood is supposed to be the longer we do this (2 years now, including 9 months of deschooling first)
