Theoretical explanation of various types of encryption and cryptographic signing, as well as practice with some command line tools to carry out simple tasks.

I would split digital privacy from the foss and Linux discussions. They attract the same people, but are fundamentally different topics.

It also means you could get deeper into the digital privacy topic which is more useful to most people.

For the digital privacy one, ask for a volunteer (or do you!) ahead of time and get them to do GDPR requests for apple, Google, Microsoft, Meta etc. sanitizer anything they want to hide, but do a demo of what big tech actually knows about them.

Then go though how to prevent that and have a discussion on the pros and cons of that data collection. (Eg I don’t care about Google data tracking as I find the Google location history really useful)

Something I often see missing from discussion on privacy is that it’s not always about you, the listener. Sometimes it’s about protecting the most vulnerable people around you. For example, someone escaping from domestic violence might have a different view on how their information is protected. People struggle to see the value in privacy because it’s not been a big problem for them personally or because they think it’s hopeless. An introduction to privacy in my view is all about teaching empathy, hope, and advocating for others.

Once they have that goal in mind, you can tie in how open source helps empower people to take back their privacy