The following game is great when teaching poetry or just wanting the students to be creative and have fun:

Students play in pairs. The teacher dictates the first line of a real song and the students have one minute to write the second line. This line must rhyme with the first line. The teacher gives the third line and the students create the forth. When the song is done, students can read or sing the song in class.

Teacher: you just make my life complete

Students: though you've got rather smelly feet

Teacher: through thick and thin, just wait and see

Students: that's the way best friends should be

source: Game On, Express Publishing