Visual representations of scientific data make these data accessible and enable students to examine the evidence used to build scientific arguments and test theories, even when the underlying data set is large or complicated. It is becoming more common in science education to use data visualizations based on data that students did not collect themselves. Teachers and instructional designers need to understand how students perceive and interpret such visualizations. This research examined the nature of students' interpretations about a colored, shaded-relief global digital elevation map useful for reasoning about a wide range of Earth processes. One hundred and ninety-six middle and high school students wrote answers to three open-ended questions while viewing the map projected on an overhead screen: “What do you think this is?” “How do you think this was made?” and “What do you think this is useful for?” Nearly half the students surveyed made no mention of topography/bathymetry or an equivalent concept. Twenty percent of the students misinterpreted the map to contain information other than elevation, including inappropriate interpretations such as water, temperature, and weather. Over half of the students did not describe any aspect of data acquisition as a component of the data map creation. In describing the utility of the map, students focused on information-retrieval tasks rather than on making inferences about Earth processes. Based on our findings about geoscience data visualization, we suggest strategies that may be beneficial in designing curriculum for teaching and learning with data maps.