Students at five city middle schools are serving a guinea pigs for a Nintendo Wii-based fitness program, which may be expanded city-wide if private funding can be found. At one school in The Bronx, 25 children have been testing the program after school for four hours a week, doing yoga and jogging in a room with five big TV screens and Wii consoles, which were donated by Nintendo. The concept really isn't so radical; last year a Manhattan gym started charging $110 for Wii personal training sessions. Lori Rose Benson, head of the Department of Education's Office of Fitness and Health Education, admits she isn't a "huge supporter" of the program, because of the cost and the limited number of children who can participate at one time. But naturally the kids love it; eighth-grader Emmanuel Goua tells the Post, "It's exciting, because you actually lose weight without even knowing it. It's a fun way to exercise." And eighth-grader Thalia Gutierrez explains, "It helps your arms and your biceps and everything. I have muscles. I even got abs, too." Now Nintendo just needs to come up with a Wii grammar game!