Family changes such as separation, divorce, re-marriage, stepfamilies. Feeling unloved or misunderstood. Fear and loneliness. Remember, it's never too early or late to start teaching your children how to cope with stress. Children suffer just as much as adults when they don't know or understand how to handle frustrations in their lives.
Parents can help and so can schools.
It's easier than you might think. Forbid violent TV shows and movies. Pets are often a good buffer, an emotional refuge for a child. Relaxed parents, who cope positively with their own stress, pass on these skills to children. Maintain a network of friends and activities outside the home.