The lake? this would certainly be an interesting class. She remembered reading about it somewhere, probably Hogwarts, a History, but she never paid it much attention. And learning about the creatures that must be in it would be fun. Upon hearing the question, the puff raised her hand in confustion. "Wait, what do you mean by included? Are you saying they built the lake? or did they find a place to build the school that already had a lake?" To her, it sounded like it was built, but that would be very strange. "Anyways, maybe they included it so they could study aquatic creatures, and so they could have a place to swim. I know they used it for ice skating a couple of years ago, and I think I read something about it being involved in a flood or something a while back."