The Turpentine Creek Wildlife Refuge is an amazing animal refuge near Eureka Springs, Arkansas a perfect stop to introduce the kids to some of Mother Nature's more impressive specimens. The park focuses on big cats and houses tigers, lions, and even bears! They even have a Liger, which is a rare lion-tiger hybrid that I'd only seen in pictures on the internet. Very cool!
Once you enter the park, you'll be amazed at how close you can get to the animals, way closer than in your typical zoo. If you can, try to visit at feeding time (typically 4 or 5 in the afternoon but it's always best to call ahead and ask before your visit). At feeding time, the animal keeps give the big cats their daily feed which brings the massive creatures only feet away from where you're standing!