When you consider how few hours of teacher/pupil contact time there actually are

Hmmm, but it's not necessarily about contact time, is it? If kids see a lot of official notices/letters/whatever that contain grammatical errors, then they gradually get the impression that those errors are at best unimportant, and at worst that they are not errors at all.

And much as I agree on the importance of parental influence, I don't see how any of your examples other than the cornflake packet could cause written grammatical errors, mav...

Hmmm (again), maybe song lyrics are on very dodgy grammatical ground, though they're too dagnabbited small for me to read these days.


But Mr Kellog was innocent, last time I checked!