When working with middle and high school teachers, I spend less time illustrating what is out there on the Net, and more time helping them realize what can be done with that information because it is digital. For instance, they can ask students to download the complete text of all of the inaugural addresses of U.S. Presidents, and then import this file into their word processors and use the find function to find occurrences of certain keywords and phrases. Students could teach themselves about history with information intensive tasks like these.
They can import tabular data on rainfall or earthquakes into a spreadsheet and then plot graphs or run statistical measurements. This can help students construct and test their own knowledge and help the teacher to present powerful ideas to the class.
There are many examples of how students (and teachers) can take advantage of the digital nature of Net-based information to give their students powerful and compelling learning experiences. You just have to show them what's possible "what they can do that they could never do before" and then, how to do it. I have an article on the Tech Learning web site on this subject.
Next Tip: Just-in-Time Curriculum Support