3+

EdHelper

This site has a multitude of different worksheets, activities, and games each categorized by subject or by grade.  I've used this site for extra worksheets and really enjoyed how they offer beginner, intermediate, and advance levels per grade.  It's helpful when accomodating for children in your classroom.  If you're not a member, you are only allowed access to a limited amount, but my school had a membership so we could all use it.  

QuizStar

Need assistance making quizzes for your class?  QuizStar is a Web-based quiz maker that enables you to create, administer and automatically grade your quizzes online!  You can incorporate media files like images, movies, and even audio so that the quizzes are more effective.  You can easily share with other teachers or administration.  

Cyberbee

This site has suggestions on how to use the web in the classroom. Sections include curriculum ideas, research tools, treasure hunts and web projects. I only saw math, science, and social studies based curriculum lessons, but the ones I looked at looked actually fun! I thought it was a bit difficult to navigate the site and find what you wanted-- but it's free!