28 years after world war 3 ended and the world is still recovering
The bombs and nukes went off and everyone that survived would never be the same. The radiation killed or transformed the living. Animals turned into hybrids and humans, well that's an interesting story.
The school was created people for people like me. Those who had been transformed by the after effects. We gained "powers" the things our parents knew as fiction. We all came to school to gain control little did we know something bigger was going on.