I would suggest rather than staying within Masai Mara proper, stay in one of the conservancies that now fringe the Mara.
In the most basic of terms these are like private, community-run wildlife reserves. Conservancy operators lease the land from local people and each local family receives a guaranteed monthly payment. The conservancy also provides employment and sets up development projects. People continue to graze their cattle but in a more controlled manner. And in return, fences are removed and the wildlife encouraged to return to the lands they were once driven out of. The conservancies have been a great success both for wildlife and local people. And, for tourists, they offer a very exclusive experience and the world's finest safaris.
Each conservancy has only a handful of very discreet high end camps and only guests of those camps can go on a safari in the conservancy, which means crowds of vehicles around a lion are non-existent.
The conservancies also allow activities not permitted within the reserve such as walking (highly recommended), bush camping, night safaris, etc. This makes them ideal for kids because it breaks up the routine and allows a little more freedom.
The safari vehicles and guides used in the conservancies are absolutely the best in the game and the wildlife populations are the equal of the actual reserve. However, there's a catch (of course...), conservation like this doesn't come cheap. All of the conservancies are superb but some names are Naboisho, Mara North and Nashulai Maasai Conservancy (this last one being slightly cheaper than the others and lots of focus on meeting local people). As for actual camps you cannot go wrong with any of them. All the conservancy camps are superb. I'm a big fan of the Basecamp offerings, Off-Beat and Kicheche. All are a little less extravagant than some of the other camps.
If you want to only visit the reserve and not a conservancy then I suggest either Basecamp Mara, Oldarpoi or you could go for a Maasai homestay in Sekenani village. Expect basic but perfectly comfortable rooms but an amazing experience. Your kids would really enjoy this.
