The authors recommend that the mentor not be a parent, even if the parent is qualified. For reasons of cost and convenience I am mentoring my kids.
I agree with potatoes that there is no general rule here - what works for some families may not for others. And of course I don't know enough about Talullah's husband or her family to be able to judge what will work for them. But although I have plenty of background in math to be able to teach DS the stuff he is learning, having a mentor makes a big difference for us. There are several reasons.
The most important pedagogical reason is that my interaction with DS is much smoother when I am the person helping him master something he has already learned than it is when I am the person introducing it to him in the first place. This is partly my shortcoming. Although I am very patient when I am teaching others, my patience wears thin with DS. When he is learning something new with DM (dear mentor?) either he listens better, or DM is not as affected as I am by the appearance DS consistently gives of not listening, or both.
Another advantage is that I get to learn things about DS that I wouldn't be able to otherwise. This actually seems to improve our relationship elsewhere. I'll use the same example. One of DS's peculiarities is that he fidgets when he is learning something new. He almost never looks at the teacher, is often doodling or hanging upside down off his chair or staring off into space. He does not give the impression of someone who is ready or able to learn. Amazingly though, I am discovering, he is. I watched the mentor explain to him the rules for order of operations, and I was sure he wasn't listening. He was all over the place. Then, he did a huge, complicated problem with exponents and nested parentheses and the whole works without a hitch. From watching this kind of interaction, I am learning not to judge the appearance of inattention as strongly as I used to.
It is also true that knowledge of higher mathematics is no qualification at all for teaching elementary or middle school math. It is a special skill to be able to break things down into their component parts, and the basic math techniques are so automatic for me now, and it has been so long since I learned them, that I can't even remember what most of the component parts are. I could learn or remember how to teach them, of course, but experience counts here too. Someone who is used to working with kids just learning this stuff will be able to see where they are going wrong if they are.
In addition to the direct pedagogical benefits, though, I think it is a great thing for him to have a young role model from outside the family whom he likes and respects and who really values education.
Finally, a third party can be much more effective in lobbying the school than I can. DM has already volunteered to help with that, and I can tell already that the school is especially receptive.
So as far as I can tell, then, this is the best setup I have come across so far given all the peculiarities of our situation. Naturally, other situations may work better for other families.
I do still wonder what to do with the school. But more on that later.
