I think that's what they're going for. It's their Monster High (except I don't think it has any shot at being that good).
so what? that would mean the only adult superheroes are men in this world...not sure how to feel about that
But these are not Barry Allen or Hal Jordan right? That's different. They're probably going with Wally West. And Beast Boy is a Teen Titan so that makes sense that he's at the school. Only a few females have been de-aged I think. I'm looking at it as its own thing so I'm not really bugged by Wonder Woman being a teen while Superman is a mature adult.
Cheetah's inclusion seems a bit random though aside from her just there to be a rival for wonder woman to deal with.....Cheetah has never been a superhero(not even teased at it...i think)so her attending a hero for superheroes makes little sense if she's just gonna be the typical bully character who doesn't even belong in a place where you train to save the lives of other people and fight crime
Consider that Monster High also has a feline antagonist, I'm sure that had some influence on the decision to include Cheetah as a student.
Toralei
But I think Cheetah's presence is also needed because conflict within the school has to come from somewhere. And it might help even more to bring in that Monster High crowd.