Tired of hauling my kids out of my bedroom watching TV when they are upstairs and supposed to be doing homework, I built a lock-out device. It is simple and under 10 bucks.
I bought a metal box at Home Depot that is supposed to be installed outside the home to house an air conditioner fuse. It is 3"x6"x10" and has a thing to accept a padlock on it. I took out all the stuff inside, and cut 2 slots on the side of it, so when open I can slide an electrical cord in, then shut the door, slot is just wide enough to allow the cord, but not wide enough to let you pull out the plug. I put the TV plug leading into the box, and an extension cord leading out. I plug extension cord into the wall. When I want the TV on I unlock padlock, open box, plug TV into extension cord. When I don't want tv on, I lock box with plug, and female end of extension cord inside.
A nice added benefit, I don't just turn on the TV every time I go into the room, the added step of unlocking box leads me to be slightly more selective in when I watch, which is a good thing, we could all use a little less TV.
I am now seriously thinking of putting a digital appliance timer on the main TV downstairs, which would only allow power to TV at pre-determined times, and locking the plug-timer-extension-cord-end inside a box. I have my eye on a nice digital timer at Walmart for 15 bucks, but I would have to move up to a larger metal box, maybe small toolbox.
Obviouly they could cut the cord and install a new plug, but they know that kind of action would mean the TV goes away for good, so they won't do that.
Is it pathetic that my kids have reduced me to locking up the TV; yes (But they are kids after all, I was just like them when I was their age) but it is effective, and better then yelling at them all the time. Once TV is truly not an option for them, they are wandering off and finding other stuff to do, whereas previously me telling them not to watch tv meant they could lay low for a few minutes until I was off doing something else, then turn it back on.
Anyway, it is an option for handy dads who are sick of arguing over TV watching time.