Effective discipline needed for 13yo ds

[bramblina]

Aaagh I've just written a huge post and lost it.
The long and the short of it is ds has little respect for dd 10 and ds 5 and tonight I sent him from the dinner table. I've had enough. He then retaliated by chopping dds toothbrush which absolutely devastated her!!! I flew upstairs and told him how disappointed I am and how his attitude is unacceptable. I told him to stay in his room and go to bed at 9.
It's gone on too long. It's eating away at dd and ds and their behaviour is deteriorating and ds got in trouble at school last week for being too rough with another boy.
What are your most effective discipline techniques? I need to get firm on him now. I've had enough.

Please.....there must be some experienced parents out there!!!

Make some (or all depending on the severity of the behaviour) privileges such as Wifi, phone, games console, pocket money, lifts, only available to him when he's earned them.

Make the consequences of poor behaviour clear and known in advance. I.e. What he'll lose, how long for and how to earn it back.

Then put the consequence in place and don't discuss/argue the toss about it.

Oldest child always has the toughest time.

And always always stick to your guns. If you've said there will be a consequence there absolutely must be.

Look at The Solihull Approach.

Do you have any idea what’s at the root of all this?
You’ve mentioned a couple in incidences but what’s he like the rest of the time?

I can second the Solihull Approach being sound too

You need to make sure that he doesn't end up feeling rejected as things will escalate.

Can you make some time just for him - help him to respect you and your disappointment will mean something. He may also be struggling with emotions and such especially as hormones on the rampage and things are coming out at home.

Thanks all.
He is a lovely boy- he's smart, wise, mature, intelligent, polite and we're super proud of him. His behaviour towards his younger siblings is our only issue really. His 1st yr (Scotland, high school) report last month was wonderful- of his 16 subjects all reported "excellent" and he knows we're delighted as we talked at length about it.

Llangenneth you think so? I wonder if we're a little soft on him and that's why he takes liberties and feels he can get away with this behaviour- because he's so good elsewhere. However i am aware of there being more on his shoulders as he's the oldest so think i understand what you mean. I worry that dd in the middle gets the hard time as she gets the least one to one time. Dh is away 5 days so I really do juggle hard.

It was ds2 (5) who got in trouble last week and what I meant was I think ds2 is feeling the amount of "dumping which ds1 does on the two younger ones.

I do think it's mostly hormones and I understand if he can't bear to be around the younger ones but his attitude towards them is unacceptable.
I'll have a look at the Solihull approach.