Although many years after the cartoon series premiered on television, young and old followers continue to see it. Characters like Ang, Katara, Soka, Tof, etc., try to save the world while the great war against the Fire tribe is taking place. Even though these children have the fate of the world in their hands you may be surprised at how young they really are.

Ang
Age can freeze if you too have been frozen in an iceberg for 100 years. Ang was only 12 years old when he disappeared and the fact that he has been frozen for 100 years makes him 112 years old.

Katara
The young woman from the water tribe is only 14 years old. This makes her skills with water use even more impressive.

Soka
Soka is 15 years old. This explains why he could not go to fight along with the other men of the water tribe.

Tof
The member of the land tribe is only 12 years old but she can reject men as many as four times her size.

zuko
The heir to the throne of the fire tribe is 16 years old during the Avar series. However, he was only 13 years old when he was sent to search for the missing avatar.

Suki
Suki has been training to be a Kioshi fighter since the age of 8, the serial porn is 15 years old.

Azula
Zuko's younger sister has a 2-year difference with him. So Azula is 14 years old.

Mai
The master of throwing knives is the middle sister of Zuko and Azula, which makes her 15 years old.

Taj Li
The acrobatic fighter is the same age as Azula (14 years old), so they were schoolmates with each other.

Source: Seventeen