Your intentions are noble, but I must point out that doing such things could violate the Constitutional Freedoms that we are blessed to have.
Everyone is innocent until proven guilty in a court of law. Yes, we do pay the price for this freedom, in that people that we "strongly believed to be odd" will commit crimes.
The only ways to really fight such heinous deeds, is to make the punishment that severe, that the offender is incapable of having the opportunity to become a repeat offender. Other than that, it comes down to the parents of a family, to hand down a good set of morals to their children. Those are the two strongest ways to prevent this, but even then, that's no guarantee.
If we were all to be thought monitored, where someone having the temptations and urges to commit horrible deeds could be busted, then the prison system would probably explode from having to incorporate the hundreds of millions of people.
Many of us weren't exactly angelic beings during our K-12 time, yet the overwhelming majority of us here haven't turned into such awful monsters.