Just like Aerbabe it was first lessson for me and I to was given a sheet of paper with standard calls. My instructor sat down with me and talked through the ATC side of things for a typical flight as part of the briefing and I furiously made notes for my kneeboard. He said not to worry and if I wasn't coping that he will jump in. The reality was he left me to it and I am sure all along that he had no intention of helping me out unless I had gone completely blank or stuffed up big time.
Personally I think leaving the R/T till later just makes it into something bigger than it really is and students will potentially work themselves up into a bit of a frenzy in anticipation of that big R/T day.