For those who find this too long, I suggest you skip to the "Bar none" graphic insert about 2/3 of the way down. I would be interested if anybody here would de

For those who find this too long, I suggest you skip to the "Bar none" graphic insert about 2/3 of the way down. I would be interested if anybody here would defend the "Guess and Check" method, because personally I find it a terrible way to teach math (though I grew up in a system that taught Math more along the lines of the Singapore system, so I may be biased).