As others have said, yes these are active. The first AT&T store I went to had difficulty locating the plan so I left emptyhanded. I chatted with a rep online and she gave me a keyword to use the next time - "session based plan."
So when I went to another store later, they were able to figure out what I was talking about. Essentially all you need is the AT&T SIM (free). Pop it in and then choose your desired plan and set it up all on the iPad. Important to note this setup is done all on the iPad - not online via the ATT site. There is no activation fee or charge for the SIM.