I originally bought the worm farm for Christian, to encourage him to join me in the garden. Didn't work.
After nearly losing the entire worm population (hard to do, worms are the easiest 'pets'), I decided that since I had the greatest interests in them, they were my job. I did try to get the kids involved, but they were not at all keen. It's a good thing the worms weren't scared to death from their squeals!
She also likes greengrocers (cicadas), but we don't like to give them to her, as she squeezes them to make them make their sound, and we feel sure it's not good for the long term health of the cicada.