It's a relatively commonly held view here on Less Wrong that school is mostly a waste of time.
I'm not going to comment on this directly. Instead I'm going to show that school probably has some impact on future life outcomes.
The evidence for this is the Relative Age Effect.
The term relative age effect (RAE), also known as birthdate effect or birth date effect, is used to describe a bias, evident in the upper echelons of youth sport and academia, where participation is higher amongst those born early in the relevant selection period (and correspondingly lower amongst those born late in the selection period) than would be expected from the normalised distribution of live births. The selection period is usually the calendar year, the academic year or the sporting season.
For example students in Oxford were well over 20% more likely to be born in September (the start of the academic year), than August (the end).
The classic explanation for this is that whilst there's not much of a difference in maturity between a 17 year old and an 18 year old, there's a large difference between a 4 year old and a 5 year old. So older kids shoot to the top of the class when they start school, and so are more likely to be engaged and interested in class, which keeps them at the top even once the difference in maturity stops being relevant.
This implies that either
A) School does something positive for those at the top of the class (pushes them up relative to kids who don't go to school at all).
B) School demotivates those at the bottom of the class (pushes them down relative to kids who don't go to school at all).
C) Given how difficult it is to get into Oxford, even 1 years worth of maturity can make a significant difference.
If we discount C, then school does have some impact on academic outcomes albeit we don't know if that outcome is positive or negative.
Further research could include:
- is there a difference between students who took a gap year before applying and those who didn't? This would investigate option C above.
- does this effect persist among home schooled children, where the classic explanation wouldn't apply.
- does this effect persist into later life outcomes? Thai would measure whether the impact is short term or long term. According to Wikipedia this effect has been observed among CEOs of S&P 500 companies as well. However this is maybe just because they're more likely to get into a prestigious university, which is what really matters, not that school directly had an impact.
Apparently at least one study found an opposite effect within the cohorts of students at a single university: https://d-nb.info/991457412/34
This study, though reminds me of the SSC post on Searching for One Sided Tradeoffs. If everyone admitted to a typical school is pre-selected for a certain overall level of ability, as visible in their applications, then the younger students in a class may have greater ability simply because their official, legible results underestimate them. Maybe?
I wonder, if we had year-round schooling instead of long summer breaks, and less once-a-year standardized testing, if schools would have started staggering class start dates? My school district had about a dozen classes within each grade, so what if instead of 12 new classes each September they had one a month, or 3 a season?