Oh dear lord that was an interesting meeting 
So we go in and HOY is there with teacher who issued detention. She had emailed ahead to say she'd be bringing someone along and was informing them out of politeness in case they wanted a second member of staff.
Basically HOY said she'd told her DS that he has a responsibility to the school to represent them at sporting events as he is part of their sporting reputation.
Friend gave her a cold stare and said they are absolutely responsible for providing him an education but when he's representing the school they put the responsibility for missed work on him. She said they can't deny that up until the missed maths he'd always done this.
She said that her DS should just suck it up that he made a mistake and got a detention and couldn't attend the revision session.
So friend said - oh, I thought detentions were for misbehaviour - not genuine mistakes?
The HOY was quite brash and kept saying that as a member of the school they expected her ds to represent them at the competitions from here on in as he'd agreed previously and that she as a parent must find a way to help him not be stressed over the GCSEs. She wouldn't actually listen to my friend saying she gets the whole detention thing was just mis communication but that itself has highlighted to her as a parent how stressed her ds is about the exams. And that as a response to that she feels missing more days out of school will add to that and so they've come to a decision together that athletics for school needs to stop.
I just say there half expecting the pair of them to start yelling at each other as neither was going to back down or discuss the situation.
Anyway it ended with the most impressive thing I've ever seen my friend do! She is one of these annoyingly organised people - she suddenly produced a copy of the letters she'd signed agreeing he could attend these events and a copy of the agreement you sign about photos, going offsite etc - she'd written the date and a comment on them saying she hereby withdraws all permission for ds to go offsite or be used by the school on the news letter or website or have his photo taken from this date onwards. She whipped out her phone and took a photo of where she'd placed it on the desk saying "as evidence you've received this" calmly looked the hoy in the eye and said that she is doing exactly what she's told her too - making sure her ds stress levels are kept as low as possible through his GCSEs and that she hoped the school would support her ds as well.
Me and the teacher were sat there catching flies!
Afterwards my friend said she had kept her trap shut since new head started and just sent her youngest elsewhere and kept quiet as she knew ds was leaving. But after the way the HOY spoke to her ds rather than ask him what he needed or offer support despite her saying he's admitted he's struggling that she said she was putting her foot down.
I have to admit I thought my friend was making a big deal about the detention thing at first - especially having read some very good reasoned posts on here - but having sat listening to HOY I now see exactly what my friends been saying about the school caring about their promotions and reputation and pastoral care being extremely poor.
Her DS is "well impressed" apparently very few people have the guts to even speak to HOY - let alone stand up to her!