I heard about this site on NPR, a search engine based on Computational Data. Ask questions about all kinds of things and get the data on them. I put in my name and it told me its rank (33rd), how many people are given my name in a year (11,342), Average age (18), and other info.
You can calculate all kind any mathematical equation and even figure out your Body Mass Index by putting in your age, height and weight. You can put in any date and get a lot of information about that date and it also tells you how long ago it was and the importance of that date. There are a ton of things you can check out on Wolfram Alapha. I think it could be used as a valuable classroom tool, check it out and see what you and your students think!