You do have to follow it up at home Di - and you want them not to just have respect at home because it needs to carry on outside - where ever he is.
Respect doesn't always go both ways in my eyes - to clarify, elders should always be respected. They aren't perfect but if it doesn't mean if they don't show you respect, that you degenerate in retaliation. I taught my daughter it's always about HER behaviour no matter what she is facing.
DD was really awful to her PE teacher (and I was called as a result) - I agreed with her stance (wanted to do soccer instead of cheerleading) I didn't agree with the way she carried on at her teacher in front of everyone.
We talked about the best ways to get your point across (and how to do it with style!), I explained how losing control and yelling means NO ONE listens to you.
Do you attend parent/teacher interviews regularly? You can get a good feel for the teachers and establish a relationship of some sorts. This way I learnt what a kind and gentle maths teacher DD had, and that her german teacher really was kind of a biartch (but she still wasn't to be rude), and told DD if she was ever unkind to her lovely soft-spoken english teacher again that she wouldn't be going out for a week.
ETA - Aww hun - getting caught smoking on the oval isn't awesome either. It doesn't matter if he doesn't want to do the work. We would all love to only do the good/easy parts in life. All the boys love the hands on part.....which will be no good to any of them if they can't spell 'automotive'.

