Let's fight it together film on Cyberbullying. A good resource which has a teacher lesson plan included and other videos on the perspectives of the characters in the video. A bit outdated with the cellphones used but still shows the cyberbullying behaviour that still continue today.
A great unit on responsible and respectful online citizenship for primary school students called "Me and the world: Being responsible online". Easy to follow lesson plans that encourage the students to think about their own online behaviour and use.