Due to "chicken math" and the darn cute factor of baby chicks each spring, you could touch on the need to quarentine new birds before adding to their established flock. Also, firmly emphasize the pecking order in a flock and the need to watch for birds low in the order who may be harassed and pecked by others. I think it is important to know that chickens will draw blood and peck another to death. It's also important to know how to treat such injuries. Basic supplies and first-aid treatment for chickens should have prime importance and a hand-out sheet.
A hand-out info sheet on acceptable treats (as an addition to their regular feed) would be good.
One thing that I keep hearing here at BYC is that a bigger coop and run with lots of room for your flock is so much better than cramped quarters that lead to stress, featherpicking, pecking, etc. And you may need to point out the need for a reliable person to give daily care to the flock if you want to ever take a few days of vacation.