A pilot study and two experiments are reported in which thematic versions of the Wason Selection Task were used to assess children's conditional reasoning. The pilot and first experiment each involved 100 eleven year olds, while the second experiment involved 36 eight year olds and 36 ten year olds. Results of the pilot suggested that 11 year olds can perform well on the full Selection Task, provided that the rules take the form of justified permissions or obligations. The first experiment confirmed this, with some of the error patterns on non justified rules being interpretable in terms of children's spontaneous judgements of costs and benefits. The second experiment established that even eight year olds can perform well with appropriate thematic versions of the Selection Task. These findings are discussed in relation to theories of contextually moderated formal competences, social contracts and pragmatic schemas, and are held to be most consistent with pragmatic schema theory.

Key words: reasoning, deduction, Wason Selection Task, pragmatic schemas