I don’t know anything about that school, but in my neighborhood Catholics are little more than a majority in Catholic schools.
Many attend due to sports. Many get scholarships (free rides) so the teams can go to Div 1 state championships year after year.
Others just go to get away from crappy city public schools.
They haven’t been to church in years.
Catholic high schools these days are more “multicultural” than dogmatically Catholic.
Are you sure about that? All kids in our parish school attend Mass every Wednesday, Catholic of not. It's the same at the H.S.