See http://industriallogic.com/papers/learning.html for a really useful suggested sequence of study for the patterns in the DesignPatterns book.

If your group is pressed for time (as ours was), and can't cover the whole book, consider the advice given on page "xv" of the book, "Guide to Readers."
It suggests starting with the "simplest and most common patterns:"
	* AbstractFactoryPattern (87)
	* FactoryMethod (107)
	* AdapterPattern (139)
	* CompositePattern (163)
	* DecoratorPattern (175)
	* ObserverPattern (293)
	* StrategyPattern (315)
	* TemplateMethod (325)