there’s already a solution to your problem. it’s called a parent. how about focusing on making them understand and account for what their kids are doing? if they can’t, the “think of the children” scope is probably bigger than just the intarweeb… I’m just sayin’…
Actions like these are always a response to the symptom and never the problem. Your kids are always going to see crap out there, and simply blocking it out doesn’t really help them shape their power of choice or will.
I’m not a parent, but I would think I would be more proud of my child if they chose not to view something on their on will, than me simply blocking it.