The purpose of this study was to identify disciplinary core ideas that should be included in secondary school agriscience programs using a panel of experts in agricultural education, and to create a matrix of disciplinary core ideas, Agriculture, Food and Natural Resources career pathways performance indicators, and the Next Generation Science Standards performance expectations. A panel of 117 experts identified a total of 162 disciplinary core ideas of STEM concepts inherent in the Agriculture, Food and Natural Resources (AFNR) career pathways. The structure for agricultural education curriculum development suggested by this research (Practices, Crosscutting Concepts, and Disciplinary Core Ideas) is supported by recent National Research Council (2012) publications. It is prudent that the agricultural education profession utilizes structures that have been proven effective, both empirically and in practice, by other related STEM disciplines. Furthermore, utilizing a structure like other STEM disciplines will aid in cross-curricular collaborations at the local, state and national levels. If agriculture educators desire to show how agriculture is a science, as an example, then the agriculture STEM matrix should reflect the framework of AFNR agriculture and science education. The matrix should serve as the foundation for addressing curricular and teacher professional development needs.