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.