Avatar: The Last Airbender - Toph Beifong's Metalbending Academy

Things are looking bright at the Beifong Metalbending Academy! But after all the adventures Toph's had with Aang, Sokka, Zuko, and Katara, the whole thing feels a bit dull. Luckily, Sokka and Suki come to visit and reintroduce some familiar faces from their wandering days. And while out and about to celebrate, Toph discovers something that just might put the sparkle back in her eye...

(Source: Avatar Wiki)