I am a school counselor that works with children ages 4-12. I have found a book by Linda Metcalf to be very helpful. I am not sure of the title (as I am not at my office now); however I know it revolves around utilizing brief solution oriented therapy in the school setting. It has numerous suggestions, activities, and counseling techniques (with a chapter on anger management). I have found it to be effective especially with the fourth and fifth grade students. Good Luck!