Idea is to build a voice/audio sensible device that will dimm the light in the room (ex. lamp), and the last action is to kill the router WiFi (ex. his power supply).
As you assumpt for kids room 
Directions/examplaes, models, boards, kits, accesorios???
tnx
What programming and/or electronics experience do you have ?
Easy solution: You say: "Geany, turn everything off" - then you press the switch on the distributor, where you hooked up all the devices earlier. Magic happens instantly
UKHeliBob:
What programming and/or electronics experience do you have ?
Programming: basic form (Pascal, Visual Basic, PHP, Java, C)
Electronic: I can save my RC car
But with Arduino i have no practical experience and I would like to learn on some project like this one and maybe trig some interest by my kids 
zwieblum:
Easy solution: You say: "Geany, turn everything off" - then you press the switch on the distributor, where you hooked up all the devices earlier. Magic happens instantly
Alexa does just that for me now. But in meantime i have to say 50-100 times to lower the voices
I would like to make things more autonomy :))
Alexa does all that now. If you really want to do it in Arduino, your biggest problem will be voice recognition. I don't recall if I've ever seen anyone do this.
Voice recognition chips for ~ 10 phrases go for ~ 10 bucks. Never used them, a physical switch is more reliable
SteveMann:
Alexa does all that now. If you really want to do it in Arduino, your biggest problem will be voice recognition. I don't recall if I've ever seen anyone do this.
No, no i dont need voice recognition.
I would like only that when the volume, noice breaches ex. 70dB that the light ist at 70% of power, and for every 30sec another -10% when it reaches -100% it kills the WiFi power (ex with relay)
"As you assumpt for kids room"
If you have out of control kids, then just go to your main router and shut down their internet access as needed to get their attention.