This resource appears to be designed to build towards this disciplinary core idea, though the resource developer has not explicitly stated so.
Comments about Including the Disciplinary Core Idea
Ideas presented in the article emphasize the ability of atoms to bond in different arrangements. The different bonding arrangements of carbon atoms in diamond, graphite, and graphene, account for the different properties of these materials. Students should be directed to this key idea with attention to Figure 2 in the resource and support with 3-D representation (physical or virtual) when available.
The article does not address how it is possible for carbon to form multiple bonding patterns creating the different allotropes of carbon. Students with prior knowledge of bonding including valence electrons and VSEPR theory should be asked to justify how different forms exist using these ideas. Alternatively, this article can motivate questions about how it is possible for carbon to bond in different arrangements and lead to further learning about valence electrons, bonding, and molecular geometry.