Freemind is a free mind mapping computer tool that is very easy to use. I found this tool very valuable for brain storming, creating lists and outlines. I used it for my list of 80 free computer tools for learners that I blogged about earlier. Freemind is not the same as concept-mapping tools that tend to by more visual, where Freemind is more based on a text outliner. What is really great about Freemind is that you and your students can download it easily and use it on computers without installing it if that if a challenge. I have used it to create an outline of notes with my learners and then posting it to the web right afterwards. I also used it as a presentation tool instead of PowerPoint to teach complicate principles and relationships.
Your students could use this tool to make and organize their notes and for developing assignments and presentations.
Go to http://freemind.sourceforge.net/ to learn more and download the tool.