Here is a clip from Nickelodeon's Avatar: The Legend Of Korra.
We also just saw a new trailer released a few days ago.
The Last Airbender: Legend of Korra takes place 70 years after Aang, starring a teenaged girl from the Southern Water Tribe named Korra.
This time the Avatar needs to finally master air, as she has earth, water and fire completed. This leads her to Republic City where she gets help from Aang's son, Tenzin.
Coming soon on Nickelodeon!