I have zero experience with school here, but I think suspension sounds completely unreasonable for his age, even if he went on the road. (What happened to the other child who "went on the road" - if the road bit is what is worthy of suspension (it isn't in my opinion) were they suspended too?) (My brother and another girl attempted to walk home when in first year of school in the UK so about 4.5 - instead of getting on the bus - they got quite a way about 1km (5km home) - there was never any disciplining of them at all only talking about road safety etc. - I will never forget the incident as I thought I was going to have to get off the bus a 9 years old and tell mum he was missing)

Apart from anything else what you want children to know is that it is dangerous to run into the road - not that it is 'naughty'.

The Yard Duty - is hard to know what to think as it obviously hasn't been explained at all - maybe they have a very good idea behind it but who knows if you are never told about it they can't expect you to just welcome it without understanding what it is about - and they obviously haven't done a good job of explaining the concept to the children if your son and the other child decided they wanted to get out of doing it that much.