Common Craft's new video could be helpful.
Digital Footprint Explained is Common Craft's latest video. The three minute video teaches viewers how they make digital footprints as soon as they go online, how digital footprints are tracked by organizations, and how to reduce the risks associated with leaving digital footprints.
Applications for Education
You and I know both know that teenagers watching this video might say something like "yeah, but if you do X, no one can track you." This video should help them understand that even those things can be tracked by law enforcement.
In related news, Common Craft is giving away three free pro accounts at the end of the month. All you have to do is be a teacher or librarian and complete the entry form here.
Disclosure: I have a long-standing in-kind relationship with Common Craft.