Attack the fun.
“Each time one prematurely teaches a child something he could have discovered himself, that child is kept from inventing it and consequently from understanding it completely.”
― Jean Piaget
Video game companies used to provide the manuals with their games in hopes kids would delve into it's arcania, become experts and dive even further into the game. Companies built levels and levels, their theory was simple: The deeper you got into the game--the more you would loved it.
The manual said: By pushing the B button and the thumb toggle at the same time your avatar could kick off the head of the ninja.
But Kids weren't reading the the manuals, what they did, was just press lots of buttons until they slowly discovered what those buttons and combinations did. They learned themselves how to kick the head off the ninja. Soon the Companies stopped producing the manuals.
And then a funny thing happened. Video games took off. Kids enjoyed them more then ever. The companies soon observed that the discovery process was totally addictive. Kids would spend hours and hours just to find a new skill, method or tactic.
Could it be that the discovery of what the buttons did was the fun part? That the level of the game you achieved was secondary? Video game companies have bet on it.
Now I have nothing against video games, but I have seen the following deprogramming techniques work in other fields to devastating effect. Remember, level of play is secondary to discovery--so it's very simple, attack the discovery, attack the fun.
HOW TO GET KIDS TO QUIT PLAYING VIDEO GAMES
Step 1) Actively get involved. Demand that your kids learn it the way the manual says. (If there is no "Manual" pretend there is one).
Step 2) Park yourself over or behind your kid and watch. beach chairs work great. Watch EVERYTHING.
Step 3) Comment on mistakes and be more demanding. Say general things like "Let's really want it!" or, "Be aggressive," or, "let's show a little hustle." This sends a friendly message that you would like to see some improvement from their video play.
Step 4) Make use of the captive audience. When they are riding in the car really drill down. Try to use specific examples of mistakes and of course stick to the manual. Say things like "It says here that if you press the B button and the thumb toggle at the same time you kick off the head of the ninja! DON'T YOU REALLY WANT TO KICK THE HEAD OFF THAT NINJA?" (OK to add a little emphasis).
At this point your child, hoping to continue playing video games, might say something like: "But, I really do want it!"
At this point refer to the manual to back up your argument "Well, you must not, because if you REALLY wanted it you would kick the head off the ninja. Your not pressing the B button and the thumb toggle, I don't think you really want it."
Step 5) repeat steps 1-4.
It won't be long before your son or daughter takes up some other activity (usually one with no manual) like skateboarding or playing in a garage band.
Your child's days of video games are over.