I am using Google Tools in my classroom. I teach A+ computer service and Cisco networking at a public technical high school. I have a one-to-one computer to student ratio. I use Gmail, Talk, Calendar, and all the Docs.
I have the browser home page to http:\\partnerpage.google.com\pcnet.jatc-sandy.org and the computers are scheduled to start the browser at login.
Instead of writing the days announcements, assignments and reminders on the white board, I use a shared document to advise the students of the day’s expectations. The calendar is great to let the students and parents know of upcoming activities. I have the students research topics and create a presentation which they then present to the class. To turn these in, they simply share them with me. I then comment directly on the presentation as feedback to the students. I have used the spreadsheet as a sign-up sheet.
I use Talk in class to take roll, the students login and when online, their icon turns green. I also use Talk in class to allow students access to me without interrupting all other students. Some students are more willing to ask a question if they feel more anonymity and less observed by their peers.
I had occasion to attend a conference while a substitute teacher looked after the class. I took the opportunity to check in on the class. Once I messaged one student to have the rest of the class to login, I was able to answer a couple questions and provide some motivation for the students to be productive while I was out of the classroom.