Know-How Exchange : E-Marketing

As strange as this may sound, my brain has 'frozen'! Everyone is telling me Blogging is a good way to get a feel for a new product/service etc... We're developing a site targeted toward Tweens - 8-12 yr olds. as it's been proven, Tweens have a vicious buying cycle - maybe not alone, however when out and about with Parent(s) or on-line they're on top of and ahead of the crowd when it comes to setting trends and being part of all the "Kool stuff". My question is how do I get in front of them to understand if this site would be of interest or even make certain they find the site... ( I hope I'm clear )? What are the Tween-Teenager 'kool sites' - if any? To draw the attention of this genre. Any suggestions, is greatly appreciated maybe some thoughts/ideas will help de-fog my brain : )