Wikipedia co-founder Larry Sanger is at it again, this time developing an educational Web resource that he hopes will transform online learning. The basic principle of his site, Watch Know, is exactly that: “You watch, you know.” The site is a video directory of educational materials geared toward 3- to 18-year-olds. It hosts materials from such popular Web sites as YouTube and Google Video. Right now, more than 12,000 videos are streamed through the site, and much like Wikipedia, Watch Know uses wiki-style collaboration to organize and share content among its users. So far, the site has generated a lot of buzz for its ability to sort educational videos. The Community Foundation of Northwest Mississippi, which funds the site, says it will expand Watch Know’s database to 50,000 videos by next year.