Purpose Over the last several decades, individuals have had access to and encountered more data than ever before. Data can be used to persuade people how to vote, support policies, adopt arguments or agendas and buy products. Data directly relate to our everyday lives including our finances, careers, educational performance and health. Therefore, it is more critical than ever for individuals and students to become data literate. This article presents a study examining the use of data visualizations in K-12 history lessons from eight popular online curricular resources.Design/methodology/approach The method employed was content analysis of 1,356 lesson plans across the eight websites.Findings About a third of the history lessons reviewed contained data visualizations, but there were mixed results across websites as to whether lesson plans provided guidance on data literacy instruction.Practical implications Because online lesson plans frequently miss opportunities to use data visualizations to deepen students’ understanding and support data literacy skills, teachers need to be aware of missed opportunities and consider ways to enhance or revise the lessons.Originality/value This study provides insight into the likelihood that history lessons found on popular online curriculum websites will support data literacy instruction. The lack of pedagogical guidance in such curricular resources underscores the importance of including data literacy in teacher education and professional development.