Here is a good visual encompassing some important netiquette rules for students to keep in mind while using the net. You might want to go through these rules with your students to make sure they understand them.
Infographic on when to use different graphic formats .jpg, .gif, .png
The Future of the Database (Infographic) – Innovation Insights
Netiquette: il galateo della rete - - infographics designed for esseredonnaonline.it- illustrated by Alice Kle Borghi, kleland.com