This restricted-use dataset contains over 260,000 open-ended student responses to 10 constructed response items from the NAEP 2017 and 2019 grades 4 and 8 mathematics assessments. The dataset includes scored student responses and demographic information for each test item. The dataset also includes student responses to other parts of the same item in other formats (e.g., fill-in, forced choice) which provide more context about the student response. This data can be used for conducting many different types of research using natural language student responses and has high accuracy in human inter-rater reliability ratings (e.g. QWK > 0.95). Data documentation is included with the dataset, such as a variable dictionary, the original version of the questions as the student would have seen them, the scoring guide/rubric for the questions, and exemplar papers used by human scorers. Your organization must apply for and be granted a restricted-use data license in order to obtain these data.