[Rosethorn tries to keep any surprise or satisfaction from being too obvious. After all, this is exactly what she said her wards were supposed to do, and she was hoping to keep the possibility of failure from making Elsa more anxious. For all she knew, Elsa's magic was different enough from hers that her own wards wouldn't recognize it.

But that smile, the sheer, giddy relief written across Elsa's face as the snow starts to ease... it's nice to see.]

It's good, that your magic's close enough to what I'm used to for my wards to recognize it. I can try training you the same way I've trained every other student I've had. There's a good chance it will help, and I certainly don't think it would do you any harm.