I believe it is not, but that's how they portrayed it in the movies...just as Durmstrang is not all-boys.  However, I may be in error because while I've enjoyed the books, I haven't gone over them with a fine-toothed comb.<br/><br/>And in any event, if it suits our GM's purposes to say things have changed in years since, then they might have done so.  ;D<br/><br/>UPDATE: I double-checked the wiki.  The books<em>do</em>apparently make references to male students at Beaxbatons.  Odds are, there are female students from Durmstrang as well.