Here are some websites that I have found helpful. The first two deal primarily with elementary, and the last two with preschool.

1) Classroom Teacher Resources
http://www.classroom-teacher-resources.com/

Classroom management section - contains tips on how to effectively manage a classroom from rules and safety to behavior management.

Classroom discipline section - gives teachers ideas on how to handle discipline in the classroom from setting expectations to tough cases.

Teacher's homeless student action center - even has a section giving teachers advice on how to help students who are homeless.

Heavy on classroom management but not light in other areas either.

2) Primary Teacher's Nook
http://www.primaryteachers.org/primary_teacher1.htm

When I first got to this website, I had my speakers turned up and the music playing surprised me. Just wanted to let you know ahead of time.

Getting started - hit the "next" button.

School notes - her website. Gives teachers an idea of how a personal school website should look.

Back to school - a classroom managment section containing links to the first day of school, planning the classroom space, literacy centers, discipline, and folder and paper control. The last section deals with topics like homework, reading logs, and work folders.

Gingerbread man - an entire section of activities and resources about the famous edible character.

Thoughout the site, the webmistress gives recommended professional books for teachers.

3) PreKinders
http://prekinders.com/

Classroom tips section - rules, schedule with description of activities, the first days of school.

Content area links - literacy, math, and science sections. Gives many helpful tips in these subjects. Also includes subjects such as art and music.

Printables section - printable templates that can be used in the classroom.

Not the fanciest looking website but effective.

4) Preschool by Stormie
http://www.preschoolbystormie.com/index.html

Teacher preparation section - many important topics including behavior management, bulletin board tips, daily schedule, disciplinary tips, and learning centers.

Curriculum section - lots of links for activities divided by month. For instance, December will have Christmas activities included.

Lots of ideas in this website.