Well, that depends on what kind of classmates they are, I guess ? Sometimes they're as close as brothers and sisters; if you don't want to upset your daughter, let her go — I don't even know what to advise.
It depends on where it is and what time of day they're meeting (it's already getting dark by 6 p.m.), but otherwise, why not. If you take all the nuances into account)))
Let her go :) but just pick her up yourselves. My aunt always lets her daughter go — I think she's 12 ? but the aunt actually drives her there and picks her up herself. And my little sister also has a watch; it seems to have GPS and a SIM card. You can check anytime where she is.