Here is a great YouTube video that summarises the reactions of the halogens.

As far as I can make out, all of the clips come from http://www.periodicvideos.com/ but the author of the video has combined a lot of these clips to put them together in one place.

Some of the reactions that are shown are off syllabus but I still think it is worth showing to the students as they get a feel for the relative reactivity of the molecules.

[youtube]tk5xwS5bZMA[/youtube]