Reform efforts in science education recommend finding ways to expand what counts as science to make classroom experiences equitable. To meet this goal, the GEMS Education Curriculum Development and Professional Learning core project partners K-12 classroom teachers, GEMS science graduate students, GEMS science faculty members, and education graduate students to co-design curriculum materials that are (1) aligned to the Next Generation Science Standards (NGSS), (2) are rooted in the science of GEMS, and (3) are social justice oriented. To design these materials, the GEMS education and outreach team hosts professional learning experiences where participants collaboratively develop units. To expand what counts as science, the professional learning activities focus on supporting participants in integrating Multiple Ways of Knowing (MWK), incorporating sustainability issues, and customizing for classroom contexts. By integrating MWK, participants can expand what counts as science by broadening students’ perspectives of what science is and who scientists are. Incorporating sustainability issues into units can lay the groundwork for supporting students to consider a variety of perspectives and knowledge to strengthen strategic action plans that can address issues in their community and beyond. Customizing units can create space for students to draw on their various Funds of Knowledge (FOK) to use as resources to support their sensemaking of intriguing phenomena. After developing materials, teachers use the units in their classroom which can provide important information for further curriculum development.