[endisneigh]

I'll have to find the research, but this generally is not true (at least with K-12).

From my recollection in general what happens is that there's a certain ratio in which low performers and high performers interact. If the ratio is stacked towards high performers in general the low performers end up doing significantly better than they would've if they were in a group consisting of people entirely like them.

This would suggest that societally there's some ratio that's optimal such that we intentionally put in "low performers" as a mechanism to raise their performance. As long as this is done very carefully it simultaneously increases the performance of low performers and maintains the potential of high performers.

Conversely if you have too many low performers and put in a high performer, not only is their potential not met, but it's generally detrimental.

In other words there's a sort of "force" pulling everyone to the mean. The "dilution" that results from adding high or low performers to an otherwise low or high performing group depends on how high or low they are and the group itself. With data this can be optimized such that low performers exceed their potential. Given the rate of change for low performers vastly exceeds high performers inherently, this is the societally optimal outcome.

That being said K-12 education isn't like higher ed is that it's lower level (intellectually).

[dolni]

Good K-12 schools _do_ batch people by ability, though. The inner city schools -- the ones that are struggling, they do a poor job putting underperforming students into remedial courses. They similarly do a poor job putting high performing students into honors and AP/IB courses.

Measuring ability is tricky, which is why schools rely on grades for prerequisite courses. As a simple, contrived example: you can't really learn how to add if you don't even know your numbers yet.

I think you're right on about K-12 being lower level is also a massive factor. I coasted through K-12, personally. I know a lot of people who did. But college kicked my ass in a lot of ways. I would argue that for higher education, matching courses to ability is _even more_ important because what you're studying is that much more difficult.

[endisneigh]

Which good schools are you thinking of? Most schools don't really do any analysis to show that they're good or not. The others are either exam schools or schools in areas that are expensive. Given the correlation between socioeconomic status and school performance, that's also just selection bias.

I'm not necessarily against tracking (which is what we're describing) - but when you have a fixed number of resources and a mentality that the best should get more resources all you really end up with is a situation where the poor students are setup to fail.

Grades pretty much exist because we decided that they need to be out of the traditional school system by 20 or so (in most school systems you can only be held back a couple of times). I disagree with grades in general but that's another discussion.

[dolni]

> Which good schools are you thinking of? Most schools don't really do any analysis to show that they're good or not. The others are either exam schools or schools in areas that are expensive. Given the correlation between socioeconomic status and school performance, that's also just selection bias.

This isn't really a scientific analysis, just basing that on my own lived experience and what I've learned from other people over the years.

I went to an inner city school. Inner city schools here offer fewer honors courses as compared to their suburban counterparts. My experience generally is that people who went to suburban schools are better educated. Suburban schools have higher graduation rates and kids get into college with more college credits than their urban peers.

> I'm not necessarily against tracking (which is what we're describing) - but when you have a fixed number of resources and a mentality that the best should get more resources all you really end up with is a situation where the poor students are setup to fail.

Well yeah, I think we're in complete agreement that some schools just don't have enough resources to do what they need to do. The goal should be for every child to realize their full potential. For some kids, that means you need to move a little slower. For others, that means you need to challenge them.

> Grades pretty much exist because we decided that they need to be out of the traditional school system by 20 or so (in most school systems you can only be held back a couple of times). I disagree with grades in general but that's another discussion.

I dunno, I think they are a useful metric for gauging ability in general terms. Not perfect. But I've yet to really see anything better.