DS is being teased most break-times by another Yr-4 boy ("K"). Among other ideas I have tried the following advice:
Ignore it: DS can't, he's too emotional.
Walk Away: K follows DS around
Tell an Adult: Not always available, K denies saying anything, K starts up again as soon as adult out of earshot
Take matter to Teacher or Headteacher: They would probably insist DS have some kind of face-2-face talk with K where DS would admit how upset he is; both DS and I hate this idea. You don't want to tell a prat just how much he's hurt you, he'll see it as a greenlight to do it even more often.
This page makes loads of suggestions, but they are all based around being witty and thinking quickly on your feet; I'm not sure DS can do that, although I will put those ideas to DS later.
In meantime I resorted to telling DS to insult back, using as few words as possible (You prat, stop being such a baby, etc.) That feels like the wrong advice, too, but what else can he do??