help! DS pinching himself "because he was so angry"

[Tommy]

DS1 is 11 and I've just noticed lots of little red marks down his arm and naturally asked him how he got them. He was very reluctant to tell me then said that he did them because he was angry because he forgot to do his HW
We had a bit of a chat about it and I suggested that if he got angry then perhaps he should punch his pillow or find something else to express his frustration (and that he should do his HW!) But.... I'm really scared .
Any advice as to how to handle it please?

anyone?

I don't have any useful idea, but I recently got the book "What to Do When Your Temper Flares: A Kid's Guide to Overcoming Problems with Anger (What-To-Do Guides for Kids)" recommended on a thread here. We've read the first chapter together and already things are a lot better. Perhaps that would help? It tells you why you are angry and how to deal with it. FWIW it says punching pillows is no good because it is an expression of anger and doesn't let you get away from it. You are supposed to think "cool thoughts" until you are less angry and then deal with the issues that made you angry. I don't know if it will work but we are giving it a try.

thanks Uptoapoint.... I'll have a look for that one. I can see where they're coming from and maybe would have said that to DS1 but it all came as such a shock that I couldn't think of what else to say.
Thank you very much