The concept is quite sound: As it is easy to bypass a lot of firewalls, and the availability and abundance of content that is not picked up by filters, a lot of net-censorship software is effectively useless against tech savvy kids.
Sentry Parental Controls has implemented a service (apart from blocking certain sites), where parents or guardians can select a range of words that they would like censored. The service then sends an email to the parent every time these words get used in search engines or appear on a website that the child has accessed.
This service also keeps track of words that are being blocked by parents, sending the data to a server owned by Sentry Parental Controls. Seeing as how children vocalise a lot of their thoughts without censorship, parents can target specific words that they would personally want to monitor. They by-product of this is that trends can be tracked as to what words are being requested most by parents, effectively keeping them abreast of what the current youth trends are and what sites need to be blocked.
They have compiled and published a list of the top 10 terms parents requested to ban. These are stats from both the USA and the UK.
Here is the list: Most of it makes sense, some of it makes me laugh and some gives a worrying insight into the current psyche of our youth and the effect of mass media in this world.