I found a website useful in science.  They provide information on the changes occuring in science through research.  Also developing publications or journals that provide information.

http://mybio.wikia.com/wiki/Main_Page

I found some Wikis that are useful in mathematics.     One wiki allows students to share with other countries what they are learning in the classroom and can compare stories.   I think it is important than you monitor who can use or  add to a Wiki.   I noticed some Wikis require a password before you can add or edit.    

http://math.wikia.com/wiki/Main_Page is the website that has companion Wikis in different languages.

I think Wikis are great tools too. I liked the one I saw where the English teacher used Wikis to teach the elements of literature. Each group had to post different elements on the wiki. What a neat modern way to teach the same things we had to learn!

Here are some great sites to use for teaching reading and other topics in the middle school classroom.

http://www.help4teachers.com/samples2.htm

http://members.aol.com/mrsscarola/middleschoolreading.html#General%20Reading%20Games

http://www.educationworld.com/a_lesson/lesson/lesson241.shtml

http://jc-schools.net/PPTs-la.html#Grades%20K-5

But my favorite is:

http://www.internet4classrooms.com/

A great website to use in the classroom with children of all ages is brainpop.com 

Have some great ideas for using the Web 2.0 applications we're discovering in the classroom?  Post 'em here!

I reviewed the Book Lovers and Literature Circle wikis and found them interesting. I particularly liked how the teacher of english set up his wiki for students taking his class. I am not sure how I would utilize this with 4th grade, especially with those who are without computers at home.

Here's an idea for students who don't have internet at home: Provide a template just like the wiki page and have them write their responses on it. They could then either simply turn in that page, or you could provide a few minutes of time for them to type it onto the wiki page the next day at school. If they have already thought it out, it should not take them more than a few minutes.

I typed in "educational wikis" in the search box at yahoo and found literally hundreds of ideas for using wikis in the classroom.  Being a book lover and teacher of english, I particulary liked the ones set up to use while studying a novel. 

I could have students make and use a wiki to explore foods of other cultures.  Maybe we could get information on foods from other regions of the US &/or other countries.  That's my Wiki classroom idea---just give me the time.

As a middle school Science teacher I know that students struggle with learning vocabulary.  I would like to incorporate vocabulary into a wiki with visuals and links to websites that teach those terms and/or have games to play.  Quizlet.com is a good website to make virtual flash cards for learning vocabulary.

A MUST see for all Elementary teachers!