When I was in school (a really long time ago), if we were caught using a calculator we'd get a zero for the day and a trip to the main office. Nowadays kids use them for tests and some are required to have them or they fail the class. No wonder that girl couldn't make change, she didn't have her calculator with her, and the register had too many buttons.
I wasn't allowed to use a calculator, either. To this day I balance my checkbook by hand. It really clears my mind --gives it a workout.