Not unlike most people, the web and all the blogs and forums provide me with so much information, ideas, and knowledge. Of course, I like to look at the open source geared sites first, and K12 Open Source (k12opensource.org) definitely receives my attention.
Going to the blog, you will find lots of ammunition to use when discussing why your school or school system should look at open source software. One thing in particular is a cost analysis looking at proprietary software vs costs of open source software. They also run a podcast, Open Source Live, where they discuss how open source can work in education. But the most helpful thing on their site is their listing of open source replacements. You can find many listings of open source replacements all over the web, but on K-12, you will find those needs of education first and foremost. For instance, they review the K12LTSP (K12 Linux Terminal Server Project). When you click on this, you see a brief little description of the project and links to the downloads and info. Good stuff!
Definitely a great resource to check when looking into open source. I trust they will continue to update the site with more and more software. Currently, you can only find about 20 packages, but this will provide a good starting place for you as you work toward more open source integration.