What I do find a little depressing about this thread is where parents' [declared] priorities lie.
If I inspire your child to learn, spend my break times working 1 to 1 to address something that they find difficult, spend my lunchtimes marking their books so that they are clear what they need to learn next and feel that their great work is praised (and also deal with the 'falling out with their friend' issue which is taking over their day, and find their lost glove, and mop up the tears when they fall over, and check that the vulnerable child in the class has lunch today, and phone a specialist teacher who is coming in to work with your child next week), teach another inspiring lesson in the afternoon, take the whole school assembly which actually gets them to think about a moral issue, speak to 4 parents after school, put up a display to celebrate your child's work very soon after they have created it, then go home to create some more inspiring lessons for tomorrow .... then that is all valueless because I have made a single, very rare for me, spelling error in a presentation.
I am not saying the spelling error is acceptable. I agree that the head or another member of staff should have a quiet word and address a training need if it exists.
However if that spelling error negates absoliutely everything else that I do as a teacher to such an extent that whatever else I do you don't respect me or regard me as having any strengths as a teacher, I feel that you might be getting things out of proportion....
(And to the poster who felt that a teacher who had not given the spelling of a presentation sufficient priority.... it depends what the 'time that could have been given to it' was spent doing, doesn't it? Vs marking books - probably. Vs spending 1 to 1 time at the end of a lesson with a child who was at risk of falling behind - maybe...but if it was your child who was the one falling behind you might have a different view. Vs an emergency child protection conference - definitely not. One of the things that makes teaching challenging is that the 'unplannable' arises on a daily basis, and even the most careful prioritisation of workload can go out of the window in an instant.