I started by 8th grade algebra class with a short explanation of Twitter. Using my Smartboard, I showed them how I was following Ed Stafford (@amazonwalkers) as they travel by foot along the Amazon River.
Then I used the site TweetVolume that allows user to choose up to five words and see a graphical representation of how many times they appear in the Twitter stream. I had groups of 4 students choose a couple of words to place in TweetVolume. We had a mini contest to see which group could determine the most popular word.
This activity is simple and is a very nice way to show a use of modern technology and graphical representation of data. It shows them another, albeit odd, use of math in the "real world". Finally, it was fun.