you probably meant it as
"because most administrative staff are female, male interests are underrepresented at the highest level"
I cant really argue with it because i've honestly no idea which male interests could possibly fall short in the context of a school, but anyway.
your phrasing of the initial statements comes across as sexism, because it sounds more like: "only males can represent all students interests"
you probably didn't mean it like that, but that what it sounds like, tbh
"Also the prevalence of women in school administration..."
Implying that male administrators, purely by being male are not making whatever nebulous errors you complain about.