I was watching Korra and got to wondering why no one did an Avatar roleplay. So here's my idea in a nutshell. After Korra died one hundred years ago, they went to look for the Avatar but couldn't find them. They did, however, find children, the descendants of the people of multiple nations, with more than one bending ability. They took these Perspectives to train them, to see which one was the Avatar, but none have been able to use all four elements. The Prospectives do the work the Avatar once did, bringing balance to the world. And so, they continue to test them, hoping to one day find the Avatar.

Technology has advance quite a bit in the last hundred years, and we now have computers, cell phones, the internet, etc.

Any child that doesn't show the ability to bend is tested at the age of five to determine if they have the potential to have bending abilities and, if so, what kind they have. This was originally done with Bloodbending (legal for testing and self defense) or by Healers, though genetic testing replaced it, as the people of any nationality can use it and it's more accurate. If the child is found to have the potential for one bending ability they are offered training in their art, both in public school and in private training if their parents can afford it. If they have the potential for more than one bending ability, though, they are given a scholarship to the nearest Prospective Academy.

Prospective Academies are closed to all but the Prospectives and their close family, if they are under sixteen. These Academies are taught by older Prospectives, and any Prospective can stay there for free if they are training, studying, teaching, or doing something else useful for the Academy. The four Academies are in Republic City, Ba Sing Se, the Northern Water Tribe, and Fire Nation Capital.

We are the Prospectives. We may not be the best Benders out there, but we will do our duty to keep the peace. Or, at least, we will try.

[hider=Why the Prospectives exist]
When Vaatu pulled Raava out of Korra and attacked her, it broke her connection to her past lives.  More accurately, however, Raava was broken apart.  Due to their being bonded to a human soul for ten thousand years, these few hundred fragments, one for each past Avatar, sought out other human souls to bond to instead of disappearing.  After those people died, their souls reincarnated into other bodies, taking their bending abilities with them.  Unlike the main piece of Raava, however, these micro-avatars wouldn't necceserily become a bender of another type when they reincarnated, and if they didn't they merely showed up as a normal bender.  As well, benders are so rare that it was unlikely that the soul of a bender would reincarnate into the body of another bender, much less do it a second time.
The avatar's soul also reincarnated, but unless the person uses multiple elements, they aren't even considered a prospective, and genetic testing will only show them to be a normal bender of their native element.
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