I think that the number one thing that I would want my students to understand about being good digital citizens is the reliability of their sources. With all of the information that is available on the Internet it will be more and more important to teach students how to decide what is "factual" and what is not. Second in importance would be having students understand copyright and fair use. Finally, I would want students to understand their accountability for what they do on the web.
I plan on using the Slideshow by Wes Fryer on Copyright and Fair Use that is linked to the SBISD Ed Tech website to discuss copyright with my students.
I think that would "teach" digital citizenship to my students by showing them the various slide shows, etc. available on the Ed Tech website and then opening up a class discussion. For the parents, I would provide links to these presentations in my weekly emails so that they too would have access to what their children are seeing.