From a recent New York Times article on teacher evalutions:
Steve Ball, executive principal at the East Literature Magnet School in Nashville, arrived at an English class unannounced one day this month and spent 60 minutes taking copious notes as he watched the teacher introduce and explain the concept of irony. “It was a good lesson,” Mr. Ball said.
But under Tennessee’s new teacher-evaluation system, which is similar to systems being adopted around the country, Mr. Ball said he had to give the teacher a one — the lowest rating on a five-point scale — in one of 12 categories: breaking students into groups.Presumably the teacher's fault lay in spending an entire class teaching the students as a whole instead of dividing them into groups. And if you know anything about current trends in education, you can guess what sorts of groups Tennessee's new teacher evaluation system expects. Only mixed-ability groups, I'm willing to bet, would have earned the teacher full points.
When it comes to heterogenous-ability-based grouping, there are all sorts of problems. The more prepared kids are bored, the less-prepared kids are intimidated; the former resent being expected to teach the latter instead of moving ahead at their own rates. These problems are particularly bad if by "grouping" one means making students work together in a group, as opposed to grouping them into different classrooms.
When it comes to classroom-level grouping, there's an alternative sort of heterogeity that (infrequent though it is) is much more effective--in part because it introduces into classrooms a novel, healthy diversity that not only avoids the problems of mixed-ability groups, but overcomes a common segregation. What I have in mind is heterogenous-age-based grouping. A school that does what it should and assigns students to particular subject levels according to readiness (i.e., according to their cognitive and academic readiness with respect to a given subject/task) will end up with heterogeneous-age classrooms.
I've seen such classrooms work quite well: the older kids provide more mature social and emotional role models for the younger kids, with the result that everyone behaves better. This also helps break down the age-segregation that pervades so much of childhood, giving all children opportunities to observe and engage with intellectual peers who are at all different levels of social and emotional maturity.
As far people in general are concerned, there are other sorts of heterogeneity we're missing out on--ones involving varieties of diversity whose benefits we rarely discuss. There's view point diversity, rarer and rare in today's sorted society; and there's neurodiversity. For all we love to rhapsodize about acceptance and full inclusion, the tolerance of our increasingly right-brained, socially-oriented society for socially awkward Aspies, rivaling our tolerance for those who don't share our political views, may be at an all-time low.