bananas.org is a GREAT web site...Has lots of information and people.

I'm still learning about growing them, so can't be much help :(

Kim, you might want to consider a superdwarf cavendish which is a very small banana species suitable for a young kid like your granddaughter. It only grows up to 2 ft tall and yes, it does bear fruit. I have some in my yard, but they haven't fruited yet. Bananas are rather temperamental plants when coming to fruiting. All you can do is to give them what they want--plenty of water and light and hope for the best. You would have to keep it as a houseplant considering the growing zone you're in. Bananas love plenty of sun, so placing them in a sunny winter during the winter months would be nice. In the summer, they'll love the heat outside. There's another species, the dwarf cavendish which grows up to 4-5 ft, but it can get rather big for a houseplant if and it might be too heavy for a 4 year old to handle. Dwarf cavendish bananas are very common and you might even find them at your local Walmart/Home Depot nursery. Hope this little bit helps and it's a wonderful thing to start kids to garden when young. My 11-year old knows most of the names of my bananas and plants and is always excited whenever we bring home a new plant for our garden.