Argh! Argumentative 12 year old!

[Woollymooly]

My son is 12. Nice, funny, bright etc. etc. But boy, does he like an argument! Especially when homework, chores and other unpleasant tasks are concerned! I know it will pass, but please, please, please tell me WHEN! It is exhausting, even asking to do 15 minutes worth of homework results in 40 minutes worth of arguments! Argh!!!!!

I tell my dd she has another 5 minutes to complain and then whatever needs to be done must be done. If she continues to whine after the 5 minutes are up then she loses a privilege.

I read somewhere there is a phrase to use. Asked and answered. Apparently it stops all the arguments. It works on my 5 year old.

Thank you, ladies for your replies.

If I take away the privilege it leads to more moaning and complaining and task is still left undone.

But Shutitweirdo - I am not sure I understood what you meant? What is "Asked and answered"?

Hello, Long and rambling post here but I have a
9 year old DS (the D is optional) who is behaving dreadfully at home. Loses his temper; lashes out at his brother and sister, backchats, screams out rude and hurtful comments; it is like he deliberately tries to annoy me e.g. exhibiting disgusting table manners ( eg.chewing with his mouth open using his hands and not his cutlery)
. He's always been a bit difficult (not very adaptable) but this behaviour has been getting worse. I am consistent in telling him when he starts behaving inappropriately he will lose privileges (mainly screen time at the weekend) and I do see it through.
It's getting when he is nice and thoughtful (which he can be for short bursts ) I just think he's just pretending to get his own way and he's being manipulative. I know I am getting into a terrible rut of feeling negative about him all the time even when he is behaving well because he loses his temper so quickly. Things can deteriorate so quickly when all is calm and three seconds later I'm in world war 3.
DS is the eldest at 9. I have a DD of 7 and another DS of 5. I have been separated from their dad for three years and he sees them infrequently (mainly school holidays)but does call and skype them every week.
I have asked DS why he behaves the way he does and he can't explain why he loses it so frequently. He blames me, his brother or sister for annoying him. He tells me he misses daddy and I can understand that but prior to our separation we spent a lot of time apart as he was working abroad and had done since DS was very little so he never was a consistent presence in the house anyway.
Last term his mouth has got him into trouble at school with his peers on two occasions that I know of as he has said some unkind things to two other boys. He was bullied at his last school and he knows what it's like to be on the receiving end of nastiness so I told him I expected better of him and was ashamed that he could behave like that. He was very contrite. Apart from these two incidents he enjoys school, he has friends and he generally behaves well in class.
Could anyone give me any insight into why he behaves the way he does. What does he get from it? How can we get past this. Are my expectations too high? I am worried about his future if he cannot control his temper.
Thanks