Sadly in high school history you only learn about WW1/2 if you take History as a GCSE option.
I've had two daughters go thru Seniors & left without knowing a thing about WW1/WW2 apart from what I've told them. (Yes they would have had to take it as a GCSE option.)
I find it disgraceful they are not taught this in general as it's a massive part of our history & should be remembered.