Background: Interest in the interactive effects of prior knowledge and text structure on learning from text is increasing but experimental manipulations of knowledge and structure variables often produce findings that do not help teachers to select expository texts for students. Aims: We aimed to extend the ecological validity of previous findings by asking students with a high or low level of discipline-relevant knowledge to read texts characteristic of those they would normally encounter. A compensation effect was hypothesized, where high prior knowledge would compensate for a lack of text structure and text structure would compensate for a lack of prior knowledge. Samples: One hundred and ninety-five undergraduate psychology students (144 Year 1 students and 51 Year 3 students) were allocated to a high knowledge (HiPK) or low knowledge (LoPK) group on the basis of their performance on a word association test. Methods: Participants were randomly assigned to one of five text structure groups (compare/contrast, sequence, classification, enumeration, generalization) and asked to study two cognitive psychology passages before recalling the main points of the text immediately afterwards and after a delay of 2 weeks. The five text structures were placed on an 'organizational continuum' according to the degree of structure/organization in the 10 passages. Results: A compensation effect did not emerge. Recall was high when texts were well structured and readers had prior knowledge, but recall was poor when texts were less structured, regardless of the level of prior knowledge. Conclusions: Readers benefit most from texts that challenge pre-existing mental representations.