Visual-spatial literacy is an essential component to developing STEM literacy, which is a primary focus of the three-dimensional Next Generation Science Standards (NGSS) framework for science education. Because scientific data is frequently communicated through visual representations, it is important for members of the current science and technology driven society to know how to analyze and interpret data presented in these forms. This study used an explanatory sequential mixed methods design to research how well K-12 science educators are prepared to teach visual-spatial literacy skills embedded within the NGSS Science and Engineering Practice 4 Analyzing and Interpreting Data. A survey was administered to K-12 science educators from one midwestern suburban school district to quantitatively assess how their instructional beliefs about when to teach visual-spatial literacy skills align with the NGSS. These quantitative data informed the development of an interview protocol that was used with a subset of survey participants to determine what experiences influence educators' knowledge of when to teach these skills. The results suggest that K-12 science educators have limited understanding about when to teach visual-spatial literacy skills needed for analyzing and interpreting data and that their level of understanding is influenced by experiences with professional development, collaboration, curriculum materials, and instructional practices focused on NGSS science education. The findings of this study highlight the importance of providing educators professional learning opportunities that address the unique needs of shifting science education to the three-dimensional approach mandated by the NGSS as successful implementation and execution of the NGSS is beneficial for developing a STEM literate populace. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://bibliotheek.ehb.be:2222/en-US/products/dissertations/individuals.shtml.]