Dr Mary Masson at the University of Aberdeen is developing web based material to help students develop the skill of writing "curly arrow" reaction mechanisms. I have had a brief look the notes and exercises on this site and commend use of the material to 1st and 2nd year students in Organic Chemistry at Bradford. Final year students may also find it worth a look.
I would be interested in learning what you think of the site.
Please Email your comments/experiences to d.j.maitland@bradford.ac.uk