Oh don't get me started, when my DD started school, she like many would leave it to the last minute before raising her hand to go to the toilet, of course the teaching staff were toooooo busy to answer a child urgently raising their hand and so she ended up having little accidents (like many others), this of course was waved around in plastic bags at the end of the day for the mothers 'walk of shame'.
My solution, I told her not to wait for the teacher, raise her hand shout toilet and take off, no more little accidents, the other children also followed suit, the classroom assistant said the teacher wasn't too happy about it but at least she wasn't having to deal with wet clothes all day.
On the other note, my daughter has AS and can still have little accidents at night, she says she can't feel when she needs to go, it doesn't wake her until she's had an accident. I don't put her in pull ups though, just protect the bed and hope she grows out of it. She can also have a little accident on the trampoline. So many children are being diagnosed with an ASD and I think sensory problems go hand in hand with that.
As for the grazed knee senario ! I was disgusted by this at DD's school, not only did they not deal with cuts and grazes most of the time they didn't bother to inform you of accidents etc. Work places are expected to have a first aider for CS so why not schools?