How long will these keep? I'm looking for a sweet to make with kids at the end of Nov. to be eaten at Xmas.

These will keep for a while since most of the ingredients are shelf-stable. At room temperature, they will definitely last until Christmas. Their flavor actually improves over time! I have never had them around that long (shelf life is not usually a problem for things that are tasty!), but I would guess that over a month they might go stale.