What about a small wallet with quilted design and CC closure or a camelia small wallet? You could get a fun color that would pop for an 18 year old.
After some research on apparently discontinued models , I moved on to the Zip Pocket Wallet from the Spring-Summer 2013 pre-collection (link below). The blue color seems to "pop for a 18 year old".
http://www.chanel.com/fashion/8-fas...in-lambskin-with-exterior-zip-pocket-3,1,4,41