This was mentioned in Byrne Hobart's newsletter. Although the points have been known for a long time, only a minority of people accept the reasoning.
I like Byrne's summary:
A good piece arguing that schools have gone too far towards detracking and ought to admit that not every student has identical interests or abilities—and that educational inequality can mean giving brilliant people more time to contribute to society. In the long run, the impact of education on success is very noisy at an individual level, but someone of an average life expectancy who attends K-12 and then gets a four-year degree will spend a little over one fifth of their life in school, so the school years themselves are a material chunk of the "long term" in question! It's easier to see why detracking is so odd if you look at it in a broader context. I haven't been in formal schooling since my early twenties, and not once since then have I ever been told that I need to listen to a lecture on something I already know, or read a book I've already read, purely because of the year on my birth certificate. This simply does not exist in the adult world, and nobody runs their life this way (unless they're subject to particular union or occupational licensing rules). Tracking by age is very convenient for information-starved bureaucracies, but if student performance is being tracked electronically, there's no excuse but inertia.
A lot of folks often conflate two separate concepts:
- tracking
- ability grouping
But they're fundamentally different.
Tracking is putting students into fixed academic paths early on. Once they're in one track, they can't switch to a different track.
Ability grouping is different. It's about meeting students where they are in each subject, with regular reassessment and movement between groups as appropriate. Math is a perfect example: it makes little sense to group purely by age when students naturally progress at different rates.
A flexible system that lets students move up or down based on their current level and learning pace isn't tracking.
Putting people on a single fixed track, with their position determined solely by their age, is stupid. We need a derogatory name for it.
I like Byrne's summary: