The plural of “me” is doubtless supposed to be “us.” From a more strictly philosophical point of view it would be “me’s.” (e.g.: There are two me’s, the evil me and the good me.)
They don’t even teach English grammar by declension any more. They didn’t even do that when I was in school. I clearly remember my Latin teacher complaining about having to teach us English before she could teach us Latin.
That’s what they meant by the plural of me, objective case plural of I.