This is a scholarly journal created specifically for history teachers, hince the title. It is full of great articles and resources that would be excellent in the classroom.
A teacher's guide to using political cartoons in the classroom at all grade levels. This web site contains an excellent collection of polital cartoons organized by artists' names and by state. This is a great tool for teaching current events and can also be included in the Language Arts, Journalism, and Art curriculum.
National Science Teachers Association - MIddle School Science. Provides science teachers with books, articles, publications, "Science Scope" journal for high school science teachers, and links to additional materials/websites for Middle School Science teachers.