Duke's Jacob Vigdor presents a nice analysis featuring the completely reasonable claim that we should individualize instruction more.
So, in a nutshell, we have the story of Americas' twin mathematics problems. Begin with a focus on inequality, and a mistaken premise that everyone could be another Einstein if they just have access to the right courses at the right time. You'll soon be patting yourself on the back for closing the gap between the best and the worst, only occasionally reminded that neither your best nor worst students are doing all that well in absolute terms. You've fallen into what might be termed the "achievement gap trap."
But see also "Make Us Do the Math".
Hacker tosses out a lot of statistics on students unable to pass algebra to support his “case,” but I don’t think anyone disagrees that this is a problem. I just can’t see how ditching algebra comprises a sensible solution. Hacker’s thinking seems to be that, because algebra is such a stumbling block for many students, we should throw up our hands and despair of ever teaching it to them. But do we really want to throw in the algebraic towel just because it’s, like, rilly hard?
This kind of experiment has already been done. We need only look to our Eastern neighbor, Japan, for a glimpse of the kind of future this could bring.