Re: who the hell is going to teach this stuff?
It may be sufficient to give the teachers a few canned lesson scripts to run through with the class, and pre-designed handouts with examples. Any kid who is likely to be interested and/or get the hang of it should be able to manage something (or at least a reasonable fraction will). Then, even if the teacher isn't really up to much, the (interested/competent) kids can do stuff off their own bat.
It doesn't have to work for everyone. Just work for those kids who are/might be interested, and whose parents aren't capable/interested/succeeding in motivating their kids in that direction.
But I'm not sure if this is BBC money well spent or not. How does it compare to the budget for Strictly? Or is Bake-Off a better comparitor? :-)