To send daughter to bed with no dinner?

With absolutely no due respect you sound awful. I'm glad you're not my mum

She calmed herself down and stayed put. She did well.

Never use holding back food as a punishment.

If you don’t want her to eat with you because of bad behaviour she still needs something simple and nutritious to eat.

Is there any chance she was ‘hangry’ after school when she lost control?

She comes down for her meal, eats quietly and goes back up to her room.

How long did you leave her in her room? Letting her languish because she complied was guaranteed to backfire either today or in the future.

after a cooling down period, you should go in and talk to her. Figure out what is going on and why she acted the way she acted. You don’t have to ask her to apologize or talk about punishment at that point. The goal should be to figure out what set her off and why she acted out.

once you understand the behavior, it’s easier to both prevent recurrence and craft appropriate punishments.

Even prisoners get food so no to withholding that. Good luck with the rest.

Sometimes I cannot believe the behaviour some parents normalise.
Dragging your child to her room and depriving her of food is Child abuse and if I knew you Id report you.
You should go up with food for her and apologise for putting your hands on her.
I cant beleive you put your hands on an 8 year old, i really cant.
Shameful, i dgif what the excuse is.
She could do the dance of the 7 veils upside naked while screaming, you should never put your hands on her.
And you do this to stop her hitting her sister? But YOU just showed here that that is how to behave.
You owe her an apology. And some bloody food fgs.
Cop on.

I feel for you.
I have one hyperactive boy (10) who is an angel at school, no concerns, very academic, passed 11+, etc. Once he gets home, he starts bouncing off the walls. What worked for us is sport clubs 5 times a week. He's calmed down a lot since then. Maybe worth a try, if you can afford it? I bet your evenings will be calmer.
BTW, lots of judgy opinions here, soon withholding a smartphone will be described as child abuse here, lol. OP is obviously struggling, I bet she has tried everything aka withdrawing electronics - it's simply not working, hence her desperation.

I am just wondering if she may need a snack straight after school. Was rattiness plus hunger maybe a trigger for the fight with her sister in the first place? I remember at that age how starving we were straight after school. In general it sounds to me as if you are overwhelmed and it doesn't sound easy by any means, but I don't think trying to find new threats and punishments that will work will help anyone.

And the difference between her hitting her sister and you "dragging her upstairs" is… what, exactly?

She’s eight. She’s not going to calm down if the adult is twice as worked up. Before everyone piles in with “CONSEQUENCES!”, it's obviously not working. You might actually get further by… well, being calm.

Try taking her to her room without the drama, sit with her until she stops fizzing, and talk to her afterwards like a human being. Reward her when she gets things right, so she’s not only hearing about it when she gets things wrong.

You’re the adult here. She’ll take her cues from you. Tell her she’s a decent kid and you don’t get why she’s acting like this, so you’re going to help her sort it out. Separate the behaviour from the child, rather than going full match-on-petrol.

She’s only 8.

I’ve seen it all on here now.
Dragging her to her room is bad enough but leaving her in her room all night alone with no food is just plain cruel.
She did wrong, she’s been punished by being sent to her room, but all night? Seriously?
My dd can be a right madam at times but I’d never send her to her room for the entire evening without food, and the fact you put “she has eaten today” makes it sound like you think this is okay?
Honestly, my heart breaks for your dd

No. No matter what, they need dinner, find another punishment.

The poster said girl had been fed. Sorry, but there have to be consequences for physical violence. My two are fully grown and happy thank you.

Yes, this, too. Is there anything the school can do to help her not have to mask so hard all day? I understand they may not be helpful if she's not causing them problems, but it's worth asking.

She's been masking all day and is completely overwhelmed. She's not choosing to be a coke bottle, she simply can't hold it together any more.
She absolutely shouldn't be hitting her sister but that is on you to intervene/distract/change the situation in whatever way works to diffuse it.
There is no way in which denying her food will help.
I have a DC with ASD & PDA (used to be called ODD until better understood) who had a couple of years of violent meltdowns. We didn't punish the meltdowns away, we connected and understood and helped and now the outbursts are minimal.

You're missing the point, it was just a suggestion of alternative wording to asking for an apology, the point being giving another way to show they are sorry without saying it. The hug is just a suggestion which may be appropriate in certain circumstances and obviously if the other child is happy with it, but may not be, hence why I said or other thing they could do to show that they are sorry.

This

I think people are coming down abit hard on you, these people also probably don’t know what it’s like parenting a child with Sen. I appreciate you’re at the end of your tether and just don’t know what else to do. Obviously you can’t leave her without food, but a talk later on and a stern warning will be good, and an apology to her sister. If you’re struggling with her behaviour school can help

As she is only 8, could you make her punishments shorter? If she went to her room and stayed there, what about going up after an hour and discuss with her if she understands her punishment. Is she willing to apologize to her sister? If yes, she can come down and the punishment is down. If not, try again later. If she relapses into the same behavior, she can go upstairs again. Repeat as needed.

I don´t think she needs more privileges removed, but needs them removed for a shorter time and given back when the punishment is done. If she acts out again, even if it's five minutes later, you can take them away again. This way she will experience immediate consequences for either good or bad behavior.

You don’t withhold food as punishment. That’s Victorian and just wrong.

Plus, how long did you expect her to stay there!? It’s ridiculous to expected her to have stayed there all evening. Your idea of punishment is extremely heavy handed!

I agree with a pp, withholding food is abusive and shouldn’t ever be used as a punishment.
Why not save her meal and call her down when everyone else has eaten and make her sit alone?

Dragging her to her room has not worked. So some feedback there from her.
Why did she hit her sister ? I would want to get to the root of that. And for an apology to happen sister to sister. Remind them to love and respect each other.
As to dinner. Absolutely feed her. Not feeding her is exacerbating the issue. And doing nothing to resolve it.

OP, what are you doing to manage this? Have you been in touch with the SENDCO to make sure there’s appropriate measures in place at school?

If just after school is a flash point then I would try and think of ways to reduce the likelihood of a clash. For example if the girls sit together in the car then separate them physically or try and have the girls walk each side of you rather than next to each other.

Could there be any possibility that a drink or snack would improve DD1’s mood? I know that some kids don’t drink much at school because they are only offered water or they don’t recognise feeling thirsty.

This sounds very typical for after-school ADHD. Have you tried adding in additional medication as it often coincides with meds wearing off.

I would get help for yourself in managing your DD and coping strategies. The normal ones won't work. And you cannot assume that what works with an NT child will work with her.

And never use food as a punishment, especially if they are on stimulants. It's hard enough keeping their weight and growth healthy.

Good luck!