I'd just like to supplement Shannon's review since I agree with it....
It's important to know everything is cash only at the Wildlife World Zoo, no credit cards. So, you'll need cash for tickets, food, the gift shop, $1 to ride the merry-go-round, $2 for the boat ride, not sure how much the train and sjyride are, and quarters so that you can get food to feed the giraffes, ducks and wild animals at the petting zoo.
I think the giraffe feeding is the best part of the experience. Watch small kids in the petting zoo...the animals are very enthusiastic about receiving their treats, not as docile as most petting zoo animals.