In reply to galpinos:
Loch insh water sports centre is great for kids, artificial ski slope, ice rink, maybe some water sports available, two good play grounds, lots of good walks and nice loch side cafe as well.
Frank Bruce sculpture trail worth a visit, can be fun for kids trying to find the different sculptures and work out what they are.
Utah lochans good for family walk as well as creag bheag hike from kingussie.
Landmark centre up by carrbridge might also be worth a visit.
And could do decent point to point walks with bus home, like to kincraig (strathspey way) via the coffee yurt which is fun place for kids to visit and finish at suie bar or kingcraig post office cafe.