Jill,

I worked in a Jewish pre-school and though we kept Kosher, we had the kids
bring DAIRY lunches as well as served DAIRY snacks.  We had a milk allergic
boy in the class, but my co-teacher wouldn't have known that meant he couldn't
have whey, casein, etc. had I not been dairy allergic and there as well to
keep my eye peeled reading the labels of everything he ate.  I personally
think that you'd be better off sending her a lunch you packed yourself.  You
could also ask the school if you could send in snacks from home for her to
have as her own "special treat" during the other kids snack time.

Just an idea,
Jen