Engrade.com – Allows teachers of any subject, for any grade, anywhere to keep a free grade book, attendance chart and more that can be accessed by students, parents and administrators.
GradeNetwork.com – Another online grade book that really emphasizes the ability for parents and teachers to stay in touch with each other by allowing parents to see grades at a glance and message teachers.
MyGradeBook.com – Features grade books, attendance records, ability for parents and students to log in to check progress and more. Offers a free 30-day trial and then changes over to a cost per-license that gets discounted with the more licenses you purchase.
OnlineSchoolReports.com – OnlineSchoolReports allows parents to log in each day and see how their child/children are doing in school. They can use the internal messaging system to talk about any concerns they may have with the teacher. Currently the service is free of charge.
JupiterGrades (formerly SnapGrades.net) – Offers free and premium versions of a grade book that can include things like parent and student access, generating reports, Spanish translation and more. Also features scalability from a single teacher up to an entire school district.
4Teachers.org – Offers multiple free tools for the use of teachers and students alike, such as online quiz generators, grading guidelines, educational video games and much more.
Blackboard.com – Pretty much a complete educational system that allows you to stay in touch with students, run tests, leave voicemails for students and much, much more.
TheClassConnection.com – Allows high school and college students to set up communities based around their classes to create flash cards, share information, message one another and more.
Digication.com – Teachers, students and administrators can set up e-portfolios to display work, assignments, resumes and more.
Haikuls.com – An online learning management system that allows you to create lessons for your class or eclass. Also allows embedding of major services such as YouTube (YouTube) and Zoho (zoho).
KEEP Toolkit – Teachers and students can set up visual representations of their work to share with others, entice new students, put them up for peer review, and more.
Moodle.org – An open source solution for a course management system that can be scaled from a single instructor to an entire institution.
TeacherTube.com – An educationally focused alternative to YouTube for teachers and students to post videos and share them worldwide with other classes and instructors.
WiZiQ.com – A white board system that allows you to teach long distance with video and voice support that can be recorded for later playback.
Classroom20.com – A social network for teachers interested in using collaborative tools in their profession.
HotChalk.com – A mixture of a learning management system and a social network where teachers can share lesson plans with one another and interact with parents and students. Be sure to check out HotChalk on an episode of Mashable Conversations.
TeachAde.com – Besides giving teachers a social network, you can also set up a blog and site about yourself to share with others.
TeacherEvents.com – A social network for teachers that also focuses on allowing teachers to discover who is going to be at upcoming teacher conferences so that they can connect while there.
Teachers.Yahoo.com – Not yet completed, Teachers.Yahoo.com will allow teachers from all over the world to save lesson plans and share them with other teachers, saving all those involved a lot of preliminary legwork.