A well-designed assessment can assist educators on site. However, suitable large-scale, standardised, multiple text comprehension assessments for primary school children are still lacking. This study addresses this gap by developing the Measure of Children’s Multiple Text Comprehension (MCMTC), which adheres to the principles of the construction-integration and multiple-document models. The test suite, comprising 41 multiple-choice and 17 constructed-response items across a range of text genres, was administered to 1,790 students in grades 3-6. The MCMTC’s internal reliability was confirmed through Rasch analysis, with satisfactory Cronbach’s alpha and suitable item-model fit values. Correlations with established tests showed small to medium effect sizes, supporting the external validity of the MCMTC. In conclusion, this study provides a tool for assessing children’s multiple text reading comprehension, facilitating a deeper understanding across different grades and genders. It also exemplifies a practical model for test development and ability estimation using the Rasch approach.