I never believed my teachers. As early as 4th grade they were treating me like a troublemaker for not following rules like their three-paragraph essay format.
I don't like the idea of having authorities on knowledge. I much prefer Montessori or Socratic teaching methods, or explorations. They're harder to do, but they produce a better understanding of the material and they allow the student to teach the teacher as well.
https://web.archive.org/web/20080717034228/http://www.handpr...
The teachers aren't completely "wrong", they were just conveying a simplification of history of pigments (also touched on in that article). It is after all true you can mix those colors and get a wide-range of colors (including a blacker black then you would with CMY). But any pedagogy that says there is such a thing as "primary" colors that make all colors is necessarily going to be wrong, even if its CMY.
You're right in that what we're taught is often incomplete or misguided. Teachers are fallible. But as a child you assume their authority implies them being correct. I reckon seeing through that illusion is an important part of growing up. And to me, part of us growing up as humanity must involve not having to rely on the authority of governing bodies.