These are some web2.0 sites. Many are interactive and all can be used by teachers of any subject at any level (with one exception). I encourage you to check them out and see if you can make use of any of them in your class. I advise starting with one you really see a way to get creative with and getting good with that one. Then, as you begin to master that one, try another.
Blabberize allows the user to upload a picture and then record something to make it talk.
Bubbl.Us is an online way to create clusters/idea webs.
Classtools.net has different useful tools. I like to use the countdown clock.
Common Craft has a number of three minute videos that cleverly explain a variety of web2.0 tools, as well as a few other needed explanations (anyone see zombies?).
Definr is the fastest definition finder on the Internet. It says so right on the page.
Delicious is a social bookmarking site. You can save websites you like, tag them, and share them with others. It is an online tool, so you can use it from any computer hooked up to the Internet.
Dropbox lets you store files online and access them on any computer or mobile device.
Edmoto is a secure social media site for students and teachers.
Emaze allows you to create animated presentations.
Free Rice is a game site, but with a difference. For every correct answer to the different online quizzes, ten grains of rice are donated to alleviate world hunger. It allows players to start at their own level and then gets easier or harder based on the answers the player gives.
Glogster is a kind of poster that is fully designed by the user. Users can incorporate text, images, music and video into their work.
Live Binders is a way to collect and present webpages on related subjects.
Make Belief Comix is a comics creation website. Users can make a short comic strip.
Powtoon allows you to create animated videos and presentations.
Prezi is a new online presentation tool that is a step beyond PowerPoints. It incorporates motion and zooming to make presentations more dynamic.
Slide Boom allows you to upload PowerPoint presentations to the web. After that, you can embed them in blogs, wikkis, websites, etc.
ToonDoo is a comics creation website. Users can make a short comic strip.
Virtual Literary Worlds is a series of links to online virtual worlds based on famous literature.
Voice Thread is a multimedia collaboration tool.
Wall Wisher is a virtual classroom bulletin board.
Wordle allows you generate text clouds.
Zamzar is a file converter. You send one type of medium to Zamzar, like a YouTube video, and convert it to another, like a Quicktime file. This is one way to get around blocks to YouTube and show your students those interesting videos you find.