Still, they are fairly young. Young enough that while some of them may say that they would have married the boy next door rather than the prince with his secrets, where all the problems came, others will say that boys are icky anyway, and they will never ever marry.
So there is only so much they could talk about the shape-shifter. To be sure, they will prattle about their lessons, but they will not, I think, be able to deduce that much. Especially getting down to the philosophical principles of shape-shifting.
Perhaps the story-teller will be able to talk with the teachers. Being older, she, and they, could work out more.