Google Calendar

I used Google Calendars to make a Calendar for the month of July.   I think this feature would be well used in a classroom.  I would personally use it a syllabus guide.  Put assignments, quizzes, and test dates on the calendar and give to the student and email the student a link to the calendar.  This way they would have two ways to access the calendar.  Also too you could make changes and announcements on the calendar online.   The calendar is a great way to keep everyone updated and informed online.