Had to name change because don't particularly want said instructor coming across my name associated with this post!!
But I'm wondering if I'm being unreasonable/silly here because EVERYONE is saying I'm a mug for putting up with this and I'm starting to wonder if they're right.
My son joined a martial arts class three years ago and it was alright at first but after a bit we started to feel a little pressured to attend competitions etc. Apart from that the class seemed to be totally centered around instructors son who was only 7 at the time. It was like "everyone, watch L, look how he does this, it's amazing ..... L will now demonstrate a kata for us ..... " etc etc and the poor lad was put in the spotlight throughout the whole class. If he did anything wrong, the instructor would shout at him for embarrassing him, making him cry etc. His daughter (11 at the time) would often be in tears after he ridiculed her, make her look silly and shouting at her because she wasn't as amazing as her brother etc. The whole class used to feel really uncomfortable. Then as his son got older, he became quite arrogent and started calling my son a wuss and a pansy etc, obviously copying off his dad and even started punching him and kicking him randomly. His father would never tell him off unless it was done in front of everyone then he made a point of saying something but it was mainly treat like a huge joke "oh look, L has beaten up D again and he's two years younger!" 
Then we started getting pressured into going to competitions all the time. He didn't drive so I took his son from Manchester to Newcastle and he didn't even offer any petrol money or anything.
So in the end my son gave it up but I'd started by this time and became quite engrossed in it. I carried on with it but the class hasn't changed much. His son became a black belt at the age of 10 and is now used to "teach". His son gets to run the warm ups which usually involve running around, picking each other up and basically doing stuff that no self-respecting adult would normally do and then he's used to actually teach sometimes meaning us adults are being "taught" by a cockly 11 year old.
Its not just the class though, I got pressured into volunteering for competition staff and the one time I couldn't make it because I was working, he went in a strop, told the head organiser that I WOULD be doing it (which then made it worse when I had to explain to him that I couldn't) and basically made a point of letting me know how I'd let everyone down.
He ignores any messages I send him unless it benefits him to reply. (For instance if I send him a message saying "When does training start after christmas?" he'll ignore it. If I sent him one saying "I can do the next competition" he'll reply with "excellent! see you there! :-) )"
He slags people off to the class if they're not there, for instance before christmas I couldn't train very often and I heard he'd said to the entire class "oh well, Mrs Mug hasn't bothered showing up again, and she thinks she's going to be grading next year?!" WTF????
I'm due to start again on Monday but I don't know if I can be arsed with it anymore.
I'm basically paying for 2 hours in which half of that involves watching his son "demonstrate"