@mmn : I believe I once saw something of yours about eletronics and kinds in the hacker space. Therefore this might be of your interest...? The resources I've used during the workshop are at the end of the post. :)
All the kids had done until this workshop was scratch and parrot drones programming. So it was a lot of fun to introduce this variety of fascinating concepts that they had never heard of.
I wanted to teach them science more than just eletronics and programming. So I walked them through physics, mathematics and computer science; Covering concepts like linear momentum, computability, uncertainty, network science, systems and control theory, etc.
In the end (10 final minutes or so), although not in the slides, we have seen a bit of ROS and watched what the robots would do in the competitions.