My friend Andy Harrop went a whole year telling his Geography supply teacher that his name was Basil Clithopps, and would have gotten away with it too if it wasn't for the tiny matter of the end-of-year reports. We had told her that Harrop was in hospital "in a coma", information she didn't bother to check until July when the shit hit the fan and Andy was suspended.

Our 6th form stats teacher was sufficiently confused by the presence of two 'Andy's in the class that Andy C's suggestion that he was to be called 'Bernard' was, in fact, taken seriously. Our teacher actually managed to forget his real name several times...

On an exchange visit to the French school our penpals went to, several of us were ushered into an English lesson. The teacher asked us our names, and one by one, we all answered "Eddie Skez" the strange thing was, this was not prearranged, and (obviously) there was no-one called Eddie Skez.