I did a lesson on limericks that I found at http://www.primaryresources.co.uk/english/pdfs/Limericks.pdf
I got good feedback after the lesson so I thought I'd share.
The teachers in my class are mostly of a high-intermediate level so they were able to do all the tasks.
First I explained to them what a limerick is, making sure they listened to a few so that they got a good feel of the rhythm.
Lines 1,2 and 5 of a limerick are longer and always rhyme. And lines 3 and 4 are shorter and also rhyme.
Then we did the 5 tasks in the worksheet together.
In Task 5, they have to make up a limerick. That was a little difficult for some, so I encouraged them to work in groups and they came up with some great limericks.