I tend to stay away from solutions that are installed on the device itself. Usually they bog the machine down or there are some instructions on the Internet on how to bypass the software.
I suggest OpenDNS. (Configured on your home router... NOT the machines)
You can sign up for free, run an agent on one of you machines that is on most of the time (to identify your network to OpenDNS), filter out adult sites etc. via categories... and up to 25 specifc domains (I block known malware redirected sites in foreign countries liked .ru, .cn. etc. no need for me to go to those sites when I can't speak Russian or Chinese except in OpenDNS you leave the "." off for a top level domain (ru cn etc.)
If there are sites you want to get to that you don't want your child to get to... then it might be worth waiting for the "Bypass" that will come with the "Deluxe" $10 a year version.
The point to this is... your kid hopefully can't hack your router... you provide protection to all of your home machines, and you aren't bogginh down your machines with garbage-ware
Of course this solution won't cover your child taking the laptop to another network.... but you could also put the agent on the laptop and force OpenDNS in the Network settings of the Laptop. Just make sure he doesn't have admin rights to the laptop.
Or, if you ONLY
want to block things for him... only configure it on his laptop and forget the router. The you could stay with the free version.
Oh... and you can turn on logging, which he can't alter since it's hosted at OpenDNS. So you know where he's been.