Within this paper I report on aspects of a study aimed at not only discovering how and when students use a graphical calculator within an Advanced-Level (pre-University) Mathematics course, and what operations and calculations they perform with such calculators, but also the depth and type of learning that takes place when students use graphical calculators. To this end I collected various types of data: interviews; observations; student e-journals; key-stroke data from graphical calculators, and combinations of all four. The key-stroke data was collected using a piece of software called "Key Recorder" that runs in the background of a graphical calculator recording all the user's key strokes. It is then possible to playback the data file to see what the user saw and determine how they used their graphical calculator. Within the paper I outline how I used the features of the "Key Recorder" software and provide an analysis of the data on one student's activities with her graphical calculator, showing how this particular student's use of her graphical calculator developed, and changed, over the course of a year. (Contains 3 figures and 7 notes.)