A fun way to introduce persuasive writing, this lesson "Suitcase of Surprise" gets students actively engaged in the power of persuasion. Stuff a giant bag or suitcase with the most random objects (old scarf, frisbee, troll, rubber gloves, whatever you can find really). Students select one object to sell inventing a purpose beyond the obvious.
This is a planning/model sheet for how to write a persuasive advertisement. Note: It is best to start this lesson with short video clips/infomercials (found online at http://www.asseenontv.com) to pull kids in and kick off the discussion of how to sell.