Internet4Classrooms - This one has IT ALL! I cannot even beging to describe how complete and easy to navigate this site is. Just go take a look, its worth the trip. Be sure to click on all links on the page, there is so much there.
 
Rubistar - RubiStar is a free tool to help a teacher make quality rubrics. 

Big 6 - Another huge site packed with ideas and information. Click on "Lessons" on the blue tab at the top of the page to link t a wide range of leveled lesson plans.

Quiz Star - With this Web-based utility, you will be able to create a custom quiz that your students can take online! If you have a lesson plan centered around Internet Web sites, or if you want students to be able to do take-home assignments over the Internet, then QuizStar is for you

ABC Teach - This site has more than 5000 free printable pages geared to Pre-K through 8th grades. The button at the top of the page allows the user to conncet to a few free abcteach tools pages.

Teacher Planet - The alphabet search on the opening page provides a quick, easy way to locate sites related to a specific topic. Take a look, there are tons of topic ideas.

Pics4Learning - This is a great site for locating photos.  Pictures are organized by easy to use categories.  This is a great site to use with the kids as all photos are school appropriate.  Saves tons of time – the kids won’t spend an entire period looking for a cool picture of a tiger, fish, food, whatever.