That's where I'm leaning, which means the entire class can be taught inside the classroom like most of the other classes are.
I would think there should be a chapter each on each "thing" kids need to know about (perhaps homes, vehicles, measurements, debugging, PCs, etc.).
In each chapter I would think it could dive down into the "systems" involved such as the cooling system for a car, or the plumbing system for a house or the electrical system for a computer.
Repair starts with debug. Debug ends with isolation of the failed component. But debug starts with understanding the systems & isolation of the failure.
Without understanding of the system, there's no repair possible unless we teach the kids to just throw parts at the problem.
Admittedly, a _lot_ of cars are fixed by people throwing parts at them! :)
My first Chrysler was a New Yorker which, as I recall, had reverse threaded lug bolts on one side, but normally threaded lug bolts on the other.
Nobody told me this. After doing the one side, I wrenched off two or three before I realized "something" was very wrong on the other side.
There were no "warning labels" in those days. :)
This is a good observation, where we could add a systems approach to how basic electronics work also (sci.electronics.repair).