1, rebellious: 9-year-old boys usually have their own independent way of thinking, thinking that their ideas are correct, not bound by their parents, not dependent on their parents, and not recognizing their education and teaching.

2. Increased initiative and challenge: The 9-year-old boy is obviously active and has the spirit and curiosity to study new things. I like to challenge things I have never done, and I have a spirit of daring to try and take risks.

3. Emotion is obvious: 9-year-old boys are prone to fall into emotions and are sensitive to people and things around them. Usually because of a small matter, I will lose my temper or feel depressed, and my mood fluctuates greatly.