They always say the first person you meet to teach you how to snowboard leaves a lasting impression. This person has the responsibility of making you come back time and time again to snowboarding.
Todays lessons are all designed to be progressional where you learn in a step by step progression and empathizes is place on moving of the lower body parts to help you ride for longer periods, saving energy. Not all people learn at the same pace so no real pretictions can be placed. After a week's of lessons most people if not all should be able to link turns and be moving on to speed control. Lessons will help you ride at a quicker progression than no lessons and prevent you from bad habits that can take a long period to correct the muscle memory.