There are several ways to handle this. My three top suggestions are
- appear to ignore it, while considering it a chance to learn
- respond with questions, excellent when the teasing is not founded in fact
- actively respond to the tone and the teasing rather than the "facts"
For example, the notebook tease. Perhaps one person really does have a lot more bugs than anyone else, or perhaps tends to forget some of them. In this case the teasing might actually be an attempt at "constructive criticism" disguised as a joke (although in this case the humour really isn't softening the blow.) On a first occasion I wouldn't respond at all, but I would ask myself later if there's a chance that in fact I should do something about my bug quantity or my forgetfulness.
Perhaps the "victim" doesn't have more bugs than others, and doesn't forget bugs. In that situation, and when needling is happening pretty regularly, I would probably ask (sweetly and with a straight face)
Why do you say that Joe? Do I have more bugs than anyone else? I don't think I do.
Joe, are you saying I forget often? Is that something we need to discuss offline? Is it really a problem for you?
The risk is that Joe will say "yes, it is a problem, you did this, this, and this, plus you have 14 bugs and nobody else has more than 3" - be prepared to find yourself in a "learning moment". But it's also possible that Joe thinks it's funny to tease the newest team member, or the youngest, or the one that threatens him, and simple fact-based approaches will make it stop.
If it goes on and on, whether it's aimed at everyone or just one victim, even if someone speaks up after each incident and contradicts the implication that the victim is often late, doesn't pay attention, forgets things etc, you can still feel worn down and hurt. At this stage I think it's perfectly ok to ignore the content of Joe's comments entirely and say something like
I feel singled out by your tone and your teasing. I would rather you didn't talk to me like that.
You've been making a lot of funny comments at my expense in this meeting. Could you stop doing that, please?
Cut it out, Joe. Nobody's laughing.
(This last comes better from a manager in the moment but can also work from a peer. Again, in the moment.)
These last two work just as well if you are sticking up for someone else - does Steve have more bugs than anyone else, Joe? - instead of do I, for example. Responses, in my experience, are better right when the bad behavior is happening than saved up for later grievance-airing.