This paper reports on a paper and pencil concept-sorting strategy that enables trainee teachers to restructure their knowledge in any one domain of science. It is used as a self-study tool, mainly to enable them to break down and understand the progression of concepts beyond the level at which they have to teach. The strategy involves listing key ideas in an increasingly complex and inclusive fashion such that a 'chain' is developed where the initial statements are simple and the final ones more complex. Evaluation of the strategy with trainees over a five-year period revealed promising potential for the strategy as a self-study tool, as well as an audit tool, enabling tutors to more easily identify misconceptions. There was some evidence that trainees found the strategy useful in preparing themselves to teach in the classroom, possibly by enabling meaningful learning to take place according to the Ausubel-Novak-Gowin theory.