It’s more than that. Let’s look at the subjects you mention, because I agree it’s a good list, but I don’t agree that it’s possible to build a curriculum in those subjects without embedding countless value judgements.
I’ll acknowledge that math is probably the least value-laden: almost by definition, it is intended to deal with only those things that are provably true with minimal reference to the external world.
You didn’t mention it, but I would think of science falls under “methods for gaining knowledge”. And I’d think it similar to math, but that too is a value judgement: a lot of what we learn when we start doing science is challenging to certain worldviews – just ask Galileo.
More generally, methods for gaining knowledge are not perfectly objective. Should we teach kids how to listen to their emotions, or only reason? And what role faith? Should we teach them to listen to their elders, or question everything? Listen to experts, or ‘do your own research’? Trust intuition, or teach cognitive biases?
It seems like you see the trouble with respect to history, and I agree that’s one of the subject where what I’m saying is clearest: history is a bunch of competing narratives that simplify a colossally large set of facts. Although, I’d argue here that it’s often easier to ‘teach the controversy’, because e.g. every war has at least two sides, and the narrative of each side was often written down at the time.
Geography has a lot of the same problems history has. That’s easiest to see considering the independent countries of southeast Asia, or the southwestern border of Israel or Russia. And as soon as we ask questions like, “why is Northern Ireland part of the UK instead of Ireland?”, we have all the problems of narrative we have in history.
Language is even worse. First, we’re choosing which language to speak. Maybe this is less a problem in the Netherlands (are there any Dutch schools that teach Frisian?), but in the US there are plenty of districts where the majority of students speak Spanish at home, not to mention native languages that have been spoken in the Americas far longer than English. Should we encourage people to be bilingual?
But there’s also a clear political choice in how we teach language. Which dialect do we teach? Is it “color” or “colour”? Is the word “ain’t” a proper word? Can I use double negatives? We end up teaching a specific dialect, and it’s usually similar to the dialect spoken by some of the students and not the dialect spoken by others.
And we can’t teach literature without books, and choosing which books we read is absolutely a value judgement. You might thing, “teach the classics!” but there is no objective list of classics, and in any case we can’t read them all so we have to pick one. Classics that show war in a positive or a negative light? Classics that portray Christianity positively or negatively? Classics that endorse or criticize systems of class and power? There’s no objective answer, it has to be a value judgement.
I present a lot of these decisions either/or, and many can be addressed by ‘teaching the controversy’. But that too is a value judgement – do we really ‘teach the controversy’ about flat earth? Luminiferous ether? Phlogiston? The humours? Some controversies just aren’t, even though there are vocal advocates for them.
There’s no escaping value judgements. When the population is culturally homogeneous, and the education just teaches the beliefs of the prevailing culture, it might feel like it’s just ‘objective facts’ and free of ‘moral values’. But it’s still teaching values and politics, it just happens to be the values and politics that everyone already agrees with. In a culturally diverse society – and with the internet we can’t avoid cultural diversity – there’s no way to avoid teaching values and beliefs that some people disagree with.
But that’s just fish noticing the water, the water was there the whole time.