Punishment for year 7 boy

I'd be seriously doubting the common sense and ability of his teacher tbh.

Permanent ban leaves you nowhere to go next. Do a week and make it clear than it's a week ban per phone call home from now on.

That said, they are very small infractions to be getting a call from the head of year about, no school I've worked in would be calling home for that. Either it's a very strict school - in which case he needs to get used to it - or they are going hard at the start of the year in an attempt to set a standard, but may relax over time.

If he's previously been well-behaved at school, then it sounds to me more like he just needs to get used to the stricter discipline and higher behaviour standards of secondary school. IME (my son is now year 8) teachers tend to be a bit stricter right at the start of term, then gradually relax once they've asserted their authority.

I wouldn't be doing any kind of punishment at home, to be honest. This kind of behaviour is for school to deal with and it sounds as though they are. I'd probably have a chat with him to make sure he understood the rules about behaviour, and see if there was anything else going on with him. I'd also make it clear that I really don't expect any further calls from school

My son has also started y7. Is your son happy or are there any problems at school? I don't know why they're contacting you about slouching etc - they should deal with that in class. Maybe have a chat with him and find out if there's underlying issues. Mine get Xbox removal for disrespect but I'd remove the phone for a week maybe - do long as there's nothing underlying.

The eating and slouching in class are school behaviours so let the school deal with it. I don't see why you would punish at home if he's already been punished at school.
As for misbehaving on the train, I'm a bit confused about this. Who told you he has been messing around on the train? Has he admitted it? Do you know what happened and why? It's not really possible to give an opinion on how to deal with this without more info. "Messing around" is a broad term. It could be barely anything or something quite serious. I'd also be much more worried about what's prompted the change in behaviour than what punishment to give but as you asked, a lifetime ban on x-box is ridiculous. What will you take away the next time he misbehaves and the time after that?

Have these people ever worked with children before? Sarcasm aside, I find it absurd that they have even called you about these "problems" unless your son is throwing his schoolmates off the train. Again, sarcasm.

A permanent xbox ban for very low level misbehaviour? That's ridiculously over the top. What would you do if he did something actually serious?

Two for those are for the teacher to sort - don't ruin your relationship and become overly punitive for nothingness issues that school should deal with.

All children mess around on the trains. How bad was it? Does it really warrant a punishment and how did you find school find out about it?

Take away phone and Xbox for a week

I wouldn’t ban the x box permanently as that’s not really achievable and you’ll probs give in so would have the opposite effect.

What about a week ban?