Marc Cardaronella just posted a great article on Catechesis and the Olympics which gives some fantastic and very usable information on how to use Information Gap Theory to engage your students. If you want to learn who you can peak your students' interest with as little as a few sentences and a question, follow the link below and spend 3 minutes informing yourself so that you can be a more effective catechist.
Marc Cardaronella's Page
PS: I just used this theory on you, so if your interest is peaked and you are going to read the article, it worked! ;-)