Wall mounting relay
It seems that there should be such things, but there are many issues.
UL approval, should be possible, but needs a large market.
Many of the "simple things" which could have educational value for kids are not there.
Now they want to switch relays from an Iphone, maybe, if they could slow down enough.
Becoming such a marketing blur of new tech toys.
This is about as close as I can find today.
Control over power line.
http://pulseworx.com/ControlModules_.htm
A next generation x10 style control.