Mauritius has some great places - didn't go there with DC's but the hotel was full of families. Good service, good food, facilities etc. Very resort based but you can do a few organised trips out eg sailing, fishing.
Iberostar Tucan in Playacar, Mexico. Have just returned from our third trip with DS (5). Very family friendly hotel and located right on an absolutely stunning beach. Check it out on tripadvisor.com. Would highly recommend
There is a direct BA flight to Turks and Caicos every Sunday, it stops at Nassau on the way but only for about an hour and you don't get off the plane. The majority of the guests are American but to me the resort does actually feel 'caribbean', probably because most of the staff are Jamaican or Dominican. It definately has a very laid back vibe and the resort grounds are very tropical.
givemeaclue yes there was a kids club - I thought it was fine, the women who ran it were absolutely lovely and really caring. Activities-wise it was quite low key; Cubans don't have masses of toys as such but they did colouring competitions, made crafts and jewellery, went on a treasure hunt, went for walks and ice cream!, played in the clubhouse which had it's own little splashpool and playpark and sang songs and did dancing.
Mine just went for a few hours here and there and as the pool and beach were so child-friendly spent the rest of the time with us.
I couldn't recommend the Maldives highly enough. We took DDs 11,8 and 7 there are the start of the year, and they had the time of their lives. We stayed at the Diva resort, and booked through Tots Too, who had masses of great advice. Direct flights HR to Male, then a seaplane to the island. DD2 declared it the most exciting thing in the world ever, and said it totally made up her mind to be a pilot or an astronaut.
Snorkelling straight off the beach. Perfect Indian Ocean. Baby sharks, huge rays. They are all desperate to go back as soon as we can.