my 2 "spinsters" are seedaholics, but i have had some luck with parsley but the only thing they will actively get excited for is chickweed. i want to try dandelions but i haven't found an area yet that i know has not been sprayed with chemicals.
my four "teens" have actually responded to broccoli and a little for celery, since discovering the chickweed. i made a game for ozzy and froot loop out of (sort of) celery. i peel off the toughest strings from the outside of a long piece. when you do this, it goes kinda curly as you pull it off. then i just tie clumps of the strings to the cage bars! they don't actually eat it but they have fun playing with the strands and then chewing through the knot. once it falls down, they ignore it. at least they get a bit of entertainment out of it! LOL! if you do try the dandelions, post back and let us know what the reaction was. good luck.