It's true that there are some things that could be taught differently to some people, but there are some things that everyone should understand. I think the current system is also a side product of resource scarcity. There is just so much knowledge to teach children and how do you decide who needs what knowledge. The other extreme would be to start dividing children at an early age based on how they seem to learn into different classes. But what could go wrong with that? Well I think it is quite simple: they change.
The idea of a better education system is relevant, but it is really hard to accomplish. I think it is too dangerous to let children, OR their parents decide if education as it is, is for them. But I hope that developments keep on happening, so that we can adjust to the modern world better and better.
It is is a tough situation because as you say, it's not the ideal for most people, but one teacher can't tutor 30 kids and teach them all privately everything they need to learn unless they go through what can be referred to as an assembly line. But it should never be assumed that everything on that assembly line is important for ever.
Difficult things.
Some more challenging of assumptions:
Why do kids need to be divided up by any classification?
Especially age group seems like a pretty arbitrary way of grouping kids together. Maybe groups need to be ad-hoc on an interest or project basis.
Why do they need to be taught any curriculum of knowledge?
Knowledge is ubiquitous, any presupposed decision of what is important knowledge or not, is bound to fail.
Experimental learning, e.g. like with Lumiar has the advantage that to realize any project, it is inevitable to learn and use the basics.
Say they want to design and build a bike, basic maths are going to be necessary, can't design a wheel without knowing about Pi e.g
It they get used to looking for knowledge and facts rather than passively sitting there and being spoonfed, it seems to me that they learn much more valuable underlying skills and a healthier relationship with knowledge.
This pull system of knowledge on an as needed basis seems to me much more reasonable than the current push system as in trying to push it all in their little head without linking it to any perceivable real world utility.
Also the assumption that you need a "teacher" for kids to learn is under attack: kids are perfectly capable of teaching themselves and others see:
https://www.edutopia.org/blog/self-organized-learning-sugata-mitra
EDIT :
Adding that the whole concept of teaching kids to be curious and to learn is pretty preposterous on its own. Kids are naturally curious and little learning machines. What schools don't like is if their interests stray from the sanctioned boring curriculum and that is where the friction starts.
Well age groups do have a developmental psychology theory going for them. A year in the life of a child is huge, someone might be slightly above or under their year's average, but how do you judge that?
As for other assumptions of learning, it's true that we decide what is important and that might not be the best way. But again it is really hard to say what would be better. Anyway, I totally agree that changes need to be made. But how do we make them so that we don't fuck over any age group or generation, since the results will be seen years after only. Kind of ethical issue already. Same as with science, we can't test everything because of ethical limitations like giving a cure to someone and not the other. :)
That's why the developing world will leapfrog the developed world eventually, you already see it with adoption of technology: found an awesome video from
Sugata Mitra
That is actually true. It is easier to experiment in regions were they haven't established a one single way.