Lots of science at this level is not taught as you say and they just teach them as fact. They teach kids about techtonic plates, dinosaurs, atoms and the planets as just facts about the universe. why separate out "evolution" as one topic that needs this rigorous standard to be taught to kids?
Evolutionary biology is particularly hard to teach from "first principles" anyway. Once you get beyond the basic natural selection definition (variation, differential fitness, heritability), there's a lot of deeply unintuitive implications that only apply situationally, or mechanisms that result from the details of complex biochemistry. It's difficult enough to teach at an undergrad level that evolutionary theory classes are usually reserved for Juniors and Seniors with some prereqs.
Evolutionary biology is particularly easy to teach from first principles. That's one of the things which makes exploring it, as a scientific process, fun.
I actually don't. I take this on a case-by-case basis. I presented both the heliocentric and geocentric theories to my kid.
Good news: He figured out which one was right quickly enough...
Bad news: ....because someone spoiled it for him
It's easy enough to show experimentally.
Atoms, we're simply wrong about. Most of the things taught K-12 are based on obsolete models like the Bohr model. That one, I'm struggling with how to teach quite a lot.
Dinosaurs and tectonic plates aren't really all that fundamental, so I'd present them as facts. I might have some fun with young earth creationism, though, if I were feeling particularly inspired.
As for evolution:
1) The theory taught in school is wrong in enough ways which matter that I do single it out. There's also a mixture of facts, hypotheses, and errors.
2) The reasoning models underlie a lot of things, from evolutionary psychology to machine learning.
3) It's politicized, and in my local school district, used to tarnish the other political side in entirely inappropriate ways.
4) My school district spends less time on tectonic plates, dinosaurs, atoms, and planets combined than they do on any of (a) evolution (b) climate change (c) critical race theory (d) virtually anything other polarized.
5) They also do it before kids are ready to engage critically.
