Those who've not heard about this program, are probably thinking the same thing.
Really, Ray? A Nickelodeon show?
I don't blame you. At first glance, a bunch of kids with magic powers seems kinda lame. Like a YA novel before those became such hot sellers. But I'd heard people of all ages, demographics, and interests, praise this show incessantly; now I understand why.
The cast of characters occupies the same entertainment of Cowboy Bebop, and Mass Effect. The story's a beautiful combination of arcs building up to an epic finale. And despite being made prior to HDTV's being mainstream, the show still looks and sounds great, with phenomenal art-direction and voice-acting. Despite finishing it weeks ago, and completing the show's follow-up, The Legend of Korra, The Last Airbender is a show I still think back to constantly, and exclusively fondly.
Minor issues such as stock-effects, predictable breaks, and earlier episodes always wrapping up arcs in one episode, pale in comparison to what the program does supremely.