Engagement: The students are co-engaging through their characters by both asynchronously and synchronously responding to each other's Facebook posts. While Facebook can be distracting, by using a tool that the students are already engaging with outside of class, they will see their classmate's character's posts show up in the general feed and prompt them to respond.
Enhancement: Facebook allows students to post different types of multi-media about their character and share their thoughts with others. It also allows the teacher to weigh in through replies and push the student's thinking. Facebook gives students an opportunity to be reflective and monitor their thinking. Note, the teacher should be modeling how to do this. Finally, Facebook allows a lot of conversation to be happening at one time, something that would be difficult to capture with only traditional learning tools.
Extension: The way that Sara set up the assignment, allows students to connect with everyday political culture and historical character's perspectives. In addition, students can participate 24/7. Finally, the students learn how to have a positive but constructive dialog online about politics.