British vs. American English: Which one?

[quote=“ploor”]That’s been my general impression, but from what I read around here, issues like in
[Class singular or plural
don’t seem to exactly be rare.

Are such situations exceptions where British English is preferred? Or, are the teachers themselves confused about the distinctions?[/quote]
That’s a case of the test makers and teachers involved being inconsistent. In my opinion, in that case it’s totally a mistake by the school and the test writers.

Unfortunately, a number of native speaking teachers who come here are not really qualified to teach grammar. The local teachers know the rules better then the natives. But I have seen few local teachers who are actually good grammarians themselves. Some know some of the rules better then some of the foreigners and start thinking they know better than all of us who come here to teach.