One of the required readings for my ECOMP 7007 class is FOCUS: Five Rules for Writing a Great Web Quest by Bernie Dodge, one of the innovators of the Web Quest. During a discussion of scaffolding, Dodge says, "In an earlier era when content was more stable..." This notion that content, and therefore information, knowledge, and understanding, can be unstable is a true construct of the information age. Being able to work with unstable content, with knowledge and understanding that may not mean the same thing, or even exist, in a few months or years, is a true 21st century challenge and an area where students need help developing the higher order thinking skills required to make sense of such a world.
Jack McLeod, as quoted at Weblogg-ed, discusses throwing away all of our current curriculum and starting to teach kids how to manage information. Perhaps this is where we are headed. I had a chemistry teacher in high school who insisted we not bother memorizing anything about chemistry. His belief was we would internalize what we needed on a regular basis (it took me ten years to forget Avogadro's number) and could look up anything else. He was very good at teaching us how to find what we needed.
We are all wrestling with just how unstable content has become. Blogs and the ability to create a community of shared meaning are a step toward sorting it all out.