I liked doing Saturday Air driving back when I was PT. It gave me a chance to see what it was like to be a driver, albeit in the tiniest capability available, and I made more money doing it. I would show up at the Airport at 5 AM, find a 500, or 800 in the yard (hope it had the keys), and then pull it inside and up to the belt. We'd wait for the Igloos to be brought in, and then unloaded at one end, then pull our area. It used to be an 8-10 hour day, but I'm sure they cut those hours way down.
As far as the driving class, or exam? Couldn't tell ya. I never had to do either back then.