Gakuen Senki Muryou

The year is 2070. Hajime, a curious and outgoing second-year class rep at Misumaru Middle School, leads what he thinks is a quiet and ordinary life in the town of Tenmo. But, one day, two events turn all of his conceptions about the world around him upside down: the appearance of a giant white mecha fighting off an apparent alien invasion, and the arrival of Muryou Subaru, a transfer student with a predilection for old-fashioned (for the time) school dress and remarkable talents for combat and use of telekinetic power. As Hajime soon discovers, Muryou isn't the only person at Misumaru with special powers and responsibilities, either. How is it all connected to the alien Galactic Federation and the strange white giant called Shingu?

[From AniDB]