This single-case study examined the effects of a graphic organizing strategy on the ability of children to improve their text comprehension abilities. Participants were six students between ten and fourteen years old with major problems in understanding what they read. The intervention intended to teach them to visually highlight key elements of a passage, and thus, to deepen their understanding of it (story mapping). An AB multiple baseline design across subjects was applied. The intervention points were randomly determined within a preset range for each participant. In accordance with the emerging trend to apply inferential statistics as a supplement to visual inspection and the calculation of effect size measures, a randomization test and a piecewise regression procedure were used to analyze the data. Results suggested that the story mapping technique was very benefi cial in improving reading comprehension of struggling learners. The potentials of the intervention as well as of the statistical tests in analyzing data from single-case studies are discussed.