Google loves teachers, so they've created a whole section just for educators.
http://www.google.com/educators/tools.html
iGoogle
Personalize your desktop and add gadgets to make it interesting/educational. Keep visiting the gadget page- new stuff is added every day. Just be sure to use it for a few days before rolling it out to the class.
Google's Directions for Personalizing your Google Page
http://www.google.com/support/bin/answer.py?answer=25551&topic=13919
Another version, with educational applications
https://docs.google.com/document/pub?id=1PyOtL94XRNWoUnUPy-v_cSXEtUBSyrRkXeScOFQFbfA
Some good Google gadgets for the classroom:
Bookmarks- This is a great way to give students a list of the sites you want them to visit, or sites you frequently use.
Timeout!- This is a timer that counts down and makes a little noise when time's up. Great if, like me, you tell the kids there are 5 minutes, and then you get sidetracked...
Phases of the Moon- Shows the phases of the moon, with pictures.
Earthquake Watch- USGS earthquake map showing recent earthquakes.
Merriam-Webster Word of the Day- Aimed towards high school or older, but interesting nonetheless.
Yahoo! Education Word of the Day- A little more approachable.
Scholastic News
Picture of the Day- There are hundreds of "Picture of the Day" widgets. Choose one based on what you are studying. I would recommend screening it for a few days just to make sure that it works reliably and doesn't pop up with anything unexpected. Most will have some sort of ad underneath, but it's free, so I won't complain. This is a link for National Geographic Picture of the Day.
Quote of the Day- Again, there are hundreds to choose from, and you can select one based on what you are studying. These can be a starting point for class discussions or writing prompts. I'd recommend screening each for a while to make sure it works reliably and doesn't pop up with any surprises. I've seen Shakespeare, Churchill, and tons of others. A few examples...
Motivational Quotes
Humorous Quotes
Literary Quote of the Day
Quick Search Tips- http://www.google.com/intl/en/help/features.html
A list of all of the Google Shortcuts
Want to practice? Or have your students practice?
Scavenger Hunt Using Quick Searching Tricks http://docs.google.com/View?id=dg4p3b28_27g2xd6mhr
Want to take advantage of even more detailed search features?
A Google a Day- A daily knowledge quest to test your searching skills!
http://agoogleaday.com/#date=2011-11-10
Search Tips Poster- post by the computers to help your students
This is a great way to cut down on paperwork. Students can work collaboratively on documents and presentations. You can share assignments with students. You can create quizzes or tests. You can survey the class or the parents. And it's all done with a minimum of paper.
Presentations
https://docs.google.com/present/view?id=dfht3275_48c9kvn8hs
Forms- The survey we did at the beginning
Docs- Setting up an iGoogle page
https://docs.google.com/document/pub?id=1PyOtL94XRNWoUnUPy-v_cSXEtUBSyrRkXeScOFQFbfA
Spreadsheets- the data from the survey
View the ideas