First off, Wordle is not the only word cloud generator out there. Sometimes sites are blocked :( in some schools and you may not have access to Wordle.net so you may want to try WordSift, VocabGrabber, ABCya!, or Tagul the next time you want your students to create word clouds. What sets them apart are the ease of use and customization options each site offers. Play around with the different word cloud online tools to see which might be the best one for you and your class.
If you need some help on how to use Wordle and other word cloud generators, or need some ideas on how you might use them during lessons, check out Peter Pappas' blog post "Building Literacy Skills with Wordle" where he not only gives step by step instructions on using the site but also ideas for application such as defining skills, summarizing skills, and comparison skills.
The collaboration Google document which today is called "47 Interesting Ways to Use Wordle" has been created by educators for educators and was started by Tom Barrett. It's an excellent source of implementation strategies for classroom use of word clouds. The coolest part...if you come up with a different use, you can add it to the Google Doc and share it with tons of teachers that visit that site daily and then you will be part of their PLN.
And for a little fun and learning - check out Guess the Wordle daily (M-F). Students will need to use their deciphering skills to figure out the topic for the Wordle each day. Today's GTW is a great one for Missouri students.
Not sure what a Wordle word cloud is....take a look at the header and the PLN image in the previous post.