A couple of decades ago, elementary schools - or teachers - routinely grouped students by ability, the better to reach all students at their level of readiness.
Critics charged that this practice trapped poor and minority students in low-level groups, and the practice fell out of favor.
But as Vivian Yee reported in The New York Times, grouping is back, reinvented by classroom teachers for the same reason teachers did it in the first place - in an attempt to serve all students better.
The National Assessment of Educational Progress found recently that 71 percent of the fourth-grade teachers surveyed grouped students by reading ability in 2009. In 1998, only 28 percent reported doing so.
The same trend was reported for teaching math.
"Teachers and principals who use grouping say that the practice has become indispensable, helping them copy with widely varying levels of ability and achievement," Yee wrote.
It turns out that the war on grouping had the unintended consequence of forcing teachers to "teach to the middle" of a wide range of readiness levels.
Jill Sears of Woodman Park Elementary in Dover, N.H., said some students breezed through assessments, got bored and acted up, while others struggled, got frustrated and acted up.