Union

Union is one of the four schools that competes in the Island Open in Mario Tennis and Mario Tennis: Power Tour]. Union is known for losing badly in the tournaments. In the Game Boy Color game, no one from Union makes it past the first round in either tournament. In the Game Boy Advance game, Union bombs the doubles tournament, and only [[Chas makes it past the first round in the singles tournament--he loses to Mynx in the second round. In the Game Boy Advance game, Union was under the impression that they were the only school that taught Power Shots.

Game Boy Color Players from Union Game Boy Advance Players from Union
 * Sammi
 * Sean (only faced in doubles)
 * Chas (only faced in doubles)
 * Mel (only faced in doubles)
 * Leon (never faced)
 * Peter (never faced)