The Travels of Wiglington and Wenks is an online virtual world for 7-14 year olds. It is based on a series of children's books by John Bittleston. It gives kids a way to really interact with history, geography, landmarks, inventions, nature, and more. They get to travel around the world and meet historical figures like Galileo, Albert Einstien, Beethoven, etc. The basic account is FREE to sign up, or you can upgrade to an Elite Quest Traveler for $5.99/month. I received a one month free upgrade in order to review the program.
My kids, and many of their friends love games like this. There are a few virtual world type games that are very popular in the local homeschool group. In our house, it was actually starting to be a problem, so I cut way back on the amount of time my children were allowed to play. Of course, if they are going to play anyway, why not make it an educational game. The problem is, my kids did not really enjoy this one. They played it for a few minutes, but then got bored. That's not to say it is not a great game, and there are probably a lot of kids who would enjoy it. I just can't really say much more about it, because the boys would not play it. There are a couple of videos you can watch here to find out more about the program to see if it will work for you. You can also read some more TOS reviews to get some other opinions.