One way to deal with the issue of anger, especially in young children who end up throwing tantrums out of frustration, is to find out what brings it on and avoid those situations if possible.
In older children, preventing anger might not be easy or possible, so teaching them how to manage those negative feelings would be beneficial. Parents can teach their kids to punch a pillow or punching bag, go for a run, draw the negative feelings, etc. as a way of releasing negative energy. Martial arts are a good way to teach children to control their feelings, so karate or judo might help some children in learning to restrain themselves.
If anger ever gets out of control to the point that it is a daily occurrence, becomes severe, and perhaps the child is destructive, a pediatric psychiatrist should be involved.