Tasks serve important functions concerning learning and assessment. Therefore, understanding the effects of different aspects of tasks is a crucial issue. The current study analyzes effects of (a) format of reading task and (b) reading text type for children with different socioeconomic backgrounds based on the data of IGLU 2006. Neither effects of an open-ended item-format nor effects of the text type can be identified. However, the hypothesized positive effect of a combination of both aspects for children with higher socioeconomic backgrounds is supported by the analyses. Results are discussed in the light of learning and instruction in elementary schools.