Are you going off your memory of having been in school yourself 30 years ago?
In my experience you're dead wrong on this. A good teacher actually teaches you things that you can't figure out on your own - that's the whole point. I've seen massive differences in how engaged my own kids are with different subjects, and how well they understand them, based on how good the teachers are
Unfortunately the curriculum in my experience 30+ year ago didn't allow a lot of time for anything other than preparing for exams.
Here's a few things that didnt happen then but should have:
1) By 20 years ago I was very concerned about what I called 'Relationship perimission /No Means No' issues and thought it was very important that these concepts were presented to kids aged no older than 12 even prior to any sex education (there is usually a gap between relationships becoming part of kids lives and sex stuff which happens a bit later).
So if I was a teacher circa 2003 I'd have volunteered to come up with some kind of consent classes as a duty of care.
It took a long time after that for consent classes to become the norm.
I still think consent is by far the most important part of sex education and if kids get that right they should be OK.
2) Concepts not being properly explained and understood as a essential part of the curriculum:
History is the best example of this.
Every time a big idea comes into a history class the teacher should stop dead and start asking the class questions and writing bulletin points on the board to make sure the kids understand what Capitalism / Colonialism / Civil Rights / Feminism / Marxism / Totalitarianism / and any other -ISM is.
e.g.
'The Scramble for Africa'...
What is colonialism?
Is it an equal relationship?
is the culture of the colonised people respected?
How Is technology a factor?
Is religion a party to colonialism?
Has colonialism happened in Europe?
Has it happened in Ireland?
How does this affect the lives of the people?
How does colonialism end?
Does colonialism still happen and what are its long term effects?
Who writes the history of colonialism - the colonised or the colonisers?
Hopefully after the teacher does this a few times with different concepts the kids will understand that these ideas are past, present and future. Comprehending this will give you the tools to analyse any situation where it occurs.
A really good teacher needs to do this all the time - but is there enough time?
There was so little detail already in secondary school history classes (in my experience anyway).
3) Children need to be told what their rights are from a young age.
As soon as children are old enough - certainly young-ish primary school age - this needs to be on the curriculum.
What are rights?
They are non negotiable and everyone should have equal rights.
Rights should be explained to kids on their level and they should be given literature for reference that should always be available to them.
Good communication is essential and no one should be allowed use a child's ignorance, innocence or lack of experience against them.
Everyone especially adults is accountable for their actions and kids need to know their is always help and there should be a neutral supportive process if they are mistreated.
I doubt any government is keen on doing this at this point - I wonder why...
All of this is pretty simple stuff. Maybe there are lots of nice people out there doing these things for decades.
Respect and good communication is really important to me - It was very lacking a few decades ago.