This paper addresses the problem of how a novice computer user, engaged in exploratory learning, accounts for the behaviour of the device. Exploratory learning is the norm for many users who encounter computers in the work place. Exploratory learners must acquire methods from a suboptimal stream of task directed behaviour and its observable effects. A candidate model of analysis, EXPL  is taken as the baseline for the development of a new model, called Explor, which employs semantic knowledge of the lexical items used in the interface to relate user actions to system responses. The strengths and weaknesses of Explor are illustrated and discussed.