IgluSki - Skiing and snowboarding holidays to chalets and hotels in Europe, USA and Canada. There are day nurseries in most resorts, with or without ski tuition as part of the deal, open to anyone. The big question about such facilities is language - not only the language skills of those running the nurseries, about which enquiries can be made, but the language of the other children, about which you've got to make assumptions. There's no such thing as an absolutely good resort for families - or an absolutely bad one, for that matter.
Any resort is worth considering.
But there is such a thing as a resort that is generally more child-friendly than its rivals, and here are some favourites. Practically all are traffic free. The French resort that demonstrated that purpose-built doesn't have to mean brutally functional. Its pedestrian centre is built in dinky traditional style, while the road that loops around it gives convenient car access to piste-side accommodation. Wengen , Switzerland - One of the original ski resorts, full of Victorian hotels and reached only by mountain railway, which is also the main lift up into the skiing.