Well, my kid, she is 10 years old, she has played Free Realms, and she absolutely loves it. Here are pros of Free Realms:
Membership on Free Realms is very cheap, and forget paying 70 dollars a month for lifetime, for a lifetime membership it only costs $35.00 and it's a ONE TIME PAYMENT! I consider this very cheap, compared to other games my 10 year old plays.
The quality is very good, it is 3D and kids can easily make friends here. Free Realms is a mostly kid-friendly game. (See "cons" of Free Realms.)
At first in Free Realms, as you know, you may choose a human or a pixie to represent you in-game. There are different types of make-up and face paint, not to mention beards and mustache(s) for boys! The hair choices are nice too. There are up-dos, and long hair, even short hair. For the pixies, there are also different wing patterns you can choose from. As for clothing, they do not have skirts, but they do have shorts. Fortunately, they only have three pairs that my daughter has mentioned and from what I have seen, they are all appropriate, meaning they do not show off her player's butt or anything. The shirts are appropriate, though they do have "midriff" shirts as my daughter says they are called. Though they do have these shirts, they do have things that can cover their bellies.
Well, there is a very strong filter on Free Realms, I have seen before when my 10 year old was in the bathroom, I walked by the computer, and there were girls saying, "i need a dayt" and "dayum" and other ways around the chat filter.
This is a very nice game for social activity, as I said before, they have a very strong filter, it blocks numbers, and there are no sexual words or activities allowed, no swearing, (though players have partially gotten past that roadblock) nothing inappropriate or unsuitable for kids.
The currency in Free Realms are Coins and Station Cash. Coins are currency that you can earn while you do battles, open chests, etc. etc.
Station Cash costs money. Though you can get game cards or just pay through the game from your credit card. It is completely safe, they do not scam, they do not steal your money, nothing negative. My daughter has had no complaints that she didn't get her station cash, or got something she didn't like.
In a short description:
Free Realms is a kid-friendly game that is appropriate for almost all ages!