To these kids' credit, they all recognize that what they're looking at is a phone of some type. They don't, however, know it's called a rotary phone. Many of them don't know how to dial with it. Most of them have no concept of the busy signal. Some get duped into trying to explain how to send a text message from a rotary phone.
Watch and feel old. Or young. Choice quote from one of the kids: "This was awesome like 20 or 10 years ago, and look how technology advanced! Now people don't even know what this is!"
Kids Reacting To Rotary Phones [Incredible Things]