There's people on this site of all different ages, who grew up in all sorts of different places. How do you know what their high-school history covered?
In my school, history was mandatory in the first year of high-school, and I think it might have been in the second year as well. Hardly anyone did it as a subject for the remainder of their high-school years.
Needless to say, the content taught in those first 1-2 years barely even scratched the surface of historical topics.