I went to HS from 1983 to 1987 and back then, civics class (freshman year) taught that the USA is a “representative democracy”. I haven’t asked anyone what year the change was made, but this lie goes back decades.
I was in HS 1964 to 1968 and we were taught that the USA is a representative republic.
I went to high school in 82 - 86. In my school the gist of what we were taught was that Western democracies weren’t pure democracies, and that the US was a Constitutional Republic that contained safeguards to protect individual rights from the threat of “democracy” - so that the basic rights of one individual could not be discarded by the whims of the majority.