So unless these charter schools have a side business selling Soylent Green made from disruptive pupils and those with learning disabilities, they're not actually improving overall results.
Isn't this is what the root comment is saying? I did not summarize the entire thing but that was my understanding of its point.
> you can achieve a net societal improvement that way.
You can improve the outcomes of the non-low-performers, but it's hard to say it's a "net societal improvement" because the low performers are also part of society.
That depends on the improvement vs loss -- IME, it is a net improvement.
With 100 students, 5 are disruptive, verbally abusive, maybe physically violent. How much does that 5% bring down the other 95%? If we remove that 5% from the other 95%, how much does the 5% lose versus the 95% gain?
IME, the gains in the 95% are miles ahead of the losses in the 5%, which makes it's net improvement.
That’s not quite the point. By excluding low performers, you can improve the outcomes of the other kids, beyond what would be possible by mixing everyone together. So you can achieve a net societal improvement that way.