In the 2009-10 academic year, I gave a skills session (on Monday 12th October 2009) on Revision Control Systems and specifically on darcs, materials for which can be found here. Part of the students' final submissions will be a darcs repository containing the revision history of the project's development.
As well as the slides and the lab sheet, you can get a cheat sheet for darcs commands and the necessary Cygwin commands to be effective on the lab computers. You can also get the darcs repository of the sources for these materials, with
darcs get http://www.doc.gold.ac.uk/~mas01cr/teaching/cis320/2009-10/revision-control