A very useful resource is the Digital Citizenship wiki, which caters for students in grades 1-12. The wiki explains more:
This is a resource for grade level teachers to prepare students to use technology appropriately and being mindful of the citizenship skills they already possess. Come back often as this WIKI will be continually updated.
There are links to topics such as cyberbullying, plagiarism and copyright as well as links to relevant videos. A very useful site which will be added to over time.