This is all from: Dörnyei, Zoltán and Murphey, Tim (2008). Group Dynamics in the Language Classroom. Cambridge: Cambridge University Press.

Four main functions of “closure”:

• Help students realize and summarize what they’ve achieved during the course
• Provide emotional finality
• Help students  think about what’s next (plan of action)
• Evaluate teacher’s work

The authors quote Tim Kemp and Alan Taylor, 1992, p. 26: “Closing is about acknowledging the past and setting a course for the future, while celebrating the moment.”