Limiting social interaction is the heart of these guidelines. Younger kids will find plenty to explore and enjoy in early MMO content without being exposed to potentially obnoxious behavior from other players. You probably wouldn't want to spend an entire game session comparing furniture inside the houses in the big city before choosing one to become "yours" -- but your kids might, and they don't need to see notoriously offensive Trade channel chat scrolling by while they're at it.
Emphasize solo play. Groups aren't necessary for exploring basic content. Help kids choose less complicated, self-sufficient classes that are suitable for soloing basic quests.
Give up some character slots. Kids are fascinated with the character creation process. Give them more than one of your precious character slots, if you can, so they can try out different looks and classes. The loss of slots is worth the joy they'll get at trying their hands at being a boy and being a girl, a fighter and a caster, a human and a beast ...
Approve character names. Your kid will be the target of much unwanted attention if they're gallivanting about town with an inappropriate name over their heads (whether it's intentional or not).
Fence off chat. Gate your child's access to chat according to age, ability and interest. For young players, turn off chat tabs completely; trust us, they'll never miss a thing. With older children, keep public chat channels turned off while allowing kids to chat with players in their immediate area. Don't forget to block in-game voice communication features.
Turn on the profanity filter. If you do have any chat features turned on, make sure you also activate profanity filters. It's not only what kids might hear but what they might assume is acceptable to repeat ...
Turn on the chat log. If your older child runs into (or initiates ... /gulp) something inappropriate in chat, he or she might be uncomfortable or even unwilling to come to you about it. Run your eye over the chat log after play sessions, so you don't have to be an over-the-shoulder eagle eye.
Block player-to-player interaction. Many games offer features that block player-to-player item trades and auto-decline group and guild invitations. (These features can seem innocent enough, until your grade-schooler finds himself spammed with guild charter signature requests or some pest keeps popping open a trade window with useless copper or junk items.)
Don't let them be pests. Even innocent silliness can intrude upon the "serious" activity of other players. Is your youngster's raucous game of hop-the-cow disrupting the mobs that nearby players are trying to hunt? Is their nonsense typing, shouting in chat or dancing on top of the mailbox annoying everyone around them? You may need to physically chaperone very young players to make sure they're not inadvertently making a mess of other players' experiences.
Review the ground rules. Discuss anything specific you'd prefer to happen or not happen: going into particular zones, grouping with others, using auction or market systems, talking with players outside of friends and family members ... whatever your guidelines may be.
Review basic internet safety. If you're planning to allow kids to play without you there watching their screens, make sure they know how to handle themselves on the internet.
Talk about password security. If you'll allow kids to log in on their own, make sure they understand how and why to safeguard your password.
Don't let familiarity and your own maturity make you complacent. You may have shrugged off rough language, pests and bullies. That level 8 Gnoll may not have terrified you, and you probably didn't cry when you died six times in a row. But remember that this is all uncharted territory for your kids ... Be there to help them through the rough spots.
Stay involved. Whether or not you're logged into the game, parents should always remain "logged in" to what their kids are up to and interested in. Give young gamers the benefit of your boundaries, your guidance, your feedback – and your enthusiasm and support .
Share the experience. It may not be your favorite way to play, but carve out some time to share the game experience on your kids' level. Start new characters that you only play when you're together, or work through the holiday events as a team. Let your budding gamer "show you the ropes" of his favorite game areas. Stop by and help out with a gold piece or two, some fancy new crafted gear or roleplay clothing or a stash of bigger bags.
When all is said and done, sure, you could limit your kids to games designed specifically for the younger set. But there's something to be said for sharing common ground. Your kids are, after all, your kids; they want to be part of your world, to participate in whatever it is that's keeping you glued to the screen. Take advantage of that enthusiasm -- it's not every family where parents and kids have so much in common. Relish your time together, whether you're running quests together or simply swapping tales about adventures from a shared world. It's a big (MMO) world out there ... Why not enjoy it together?