I'm a homeschool mom. I've been using lessonplanet.com and recommending it to other parents in my homeschool group and other homeschool support circles for over a year now. It's easy to search, save, view, move around, very informative ratings, amount of files found in each subtopic. What I like most of all and keeps me coming back is NO SPAM EMAILS. All other sites send constant emails that clog up my real business email... educating my daughter!