The Carolina Raptor Center may be a bit of a drive, but it's totally worth it if you're looking for something different to do on a Saturday afternoon.
When you first arrive (parking can be a little tough, so go early), you walk into the main building where you can pay admission and they give you a map. Everything is self guided along a trail, and the birds are grouped together (i.e. Hawks, Eagles, Owls). Within a grouping, you can see a variety of different birds up close. It's not every day that you can walk up to an area and literally look a large hawk in the eye from less than 10 feet away. You can really see the detail on each bird being that close!
The part I like most about the Carolina Raptor Center is that each bird has a story and a name. It gives the visit a bit of a more personal experience. I enjoyed seeing how long the birds were there (two birds have been there since 1987!!!), what happened to the bird and how they were helped to keep them alive. Some of the stories are a bit sad on how the birds got there, but the happy ending of knowing that they have a safe home at the Raptor Center (when they are unable to survive on their own in the wild).
This is perfect for a 1-2 hour trip on a weekend if you want to go by yourself, with a friend or with kids. I personally took my parents there and they loved it...was their favorite part of their trip to Charlotte.