Students in most public schools don’t even learn English grammar now in most states. That went away at some point in the Bush or Obama administrations, probably due to the NCLB and Common Core initiatives. It is not uncommon now to encounter college students who simply have never heard of a “direct object.” They need classes on the grammar of their own language more than they need a school subject on interacting with an overhyped and underperforming Siri.
Common Core has English grammar as a foundational skill. Your specific example is taught in grade 5.
That said, English is a difficult language and I'm not at all surprised that people get through school without fully grasping the names for grammar concepts, even if they use them every day.
