If I understand correctly, this is a private (private in the US sense, meaning, not with federal funds) school that bills itself as "all girl". Why did the school violate its charter?

There are a number of schools and classes in the US that in recent years have gone to one-sex presentations on the basis of getting better results from both sexes. A good case, they claim, can be made that everybody should go back to that.

As for this 'all-girls' school, it says that it has 250 members of which only 36 are boys. Why are the boys there? Just for the revenue? A large price to pay for false advertising.

If, for whatever reason, I felt it necessary for my daughter's well being to send her to a single-sex school and I was paying for that service I would be seriously miffed if I found that they were slippig others in.