It's called group homeschooling. Where I grew up it was more commonly done on a class-by-class basis (e.g. several homeschooling families with teenagers would band together to hire a physics tutor) or for field trips (e.g. three moms with vans would drive fifteen kids to the museum, next month some of the dads would organize a tour of a construction site, etc.)
It can also be really good for families with a mix of school-age kids and toddlers. You get together one afternoon a week, and one parent minds the toddlers while the older kids do a craft project, a history lesson or something with the other parents. Think of it as combined school/playdate.


20 contact hours a week though? Maybe these families want the educational flexibility of homeschooling, but can't afford to have one parent stop working, or... not sure. I could also see it as a good option for people who know they are only here for a year or two (hence local schools not the best option), but aren't on the sort of salary that would enable them to afford international school fees for several kids.

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