Ah I can vent on my only mildly related recent occurrence!
DD is Yr 3 and they get spelling every week to learn and do a test. They have a sheet with cover write check, and do 3 times, then I usually run through it to see if she can spell them as we realised she does better in the tests that way.
Anyway one of them was spelt incorrectly the US way rather than English can't remember what it was it had a "z" instead of an "s". So I ummed and arred (teach DD correct but will this undermine school a little bit) anyway in the end I told her that was US spelling and we spell it like this, and I put a little note at the top of the spelling sheet to say it was US spelling and we had taught UK. I assumed that it had been printed from a US site / a US spellchecker had gone over it. So, you know, it happens. But OTOH when they are learning spellings you want them to be right? Anyway.
DD spelt it the English way in the test and was marked wrong, she (blimey brave) said to the teacher is this wrong really isn't it the English spelling and teacher said you must learn and spell it the way it is on the sheet.
So, wasn't really happy about that. On the one hand I don't want to undermine the school by saying a spelling on the sheet was wrong, but I don't want to DD to learn the wrong thing. And, I can understand why the teacher did that, but it seems harsh. She could have said to the class it was spellcheck sorry this is US spelling the correct English one is this? Don't know. I know they don't have an easy job.
We have also had 2 impossible maths homeworks and 2 that were so ill thought out they might as well have been impossible, I wasn't very happy about that either. They are resource printed from somewhere, I'd have thought primary school resources would have been really carefully checked before going online apparently not 