I work in a startup where each week, a member of the team does a short presentation (30-60 min) on a subject in front of the others. It is a very informal and relaxed session, but now it is my turn and as an intern, I feel concerned about being boring and failing to show my colleagues the interesting features of the subject I picked, which is the programming language Scala. They are all familiar with Java (on which Scala is based) but probably not with functional programming.
So, here is my question: How should I do my presentation to actually entertain them and have them learn some useful bits ? For instance, which kind of "live" examples / exercises could be interesting to demonstrate the particularities of the language?