Moodiness is short-lived and infrequent. Activity, appetite, and energy levels increase. They can be loud, rude, boorish. They like to take chances and defy rules. They like to argue with adults, yet they can be cooperative and friendly.
Friends are very important, and opposite-sex interests emerge.
They tend to avoid complicated tasks. Those not entering puberty remain much as they are. Rapid growth may cause tiredness, moodiness, bickering, and over-anxiousness.