This site, for me, is an oldie but a goodie: Science News for Kids. As their site states:
“Science News for Kids is a new Web site devoted to science news for children of ages 9 to 14.
Our goal is to offer timely items of interest to kids, accompanied by suggestions for hands-on activities, books, articles, Web resources, and other useful materials.
Our emphasis is on making the Web site appealing by offering kids opportunities to comment on and grade the subject matter, get ideas for science projects, and try out mathematical puzzles. At the same time, we offer teachers creative ways of using science news in their classrooms.”