This study addresses three key problems affecting science teacher education: preparing teachers to teach about climate change, including marine science topics in K-8 science instruction, and the effective use of the Next Generation Science Standards (NGSS), as we approach the tenth anniversary of their launch. Climate change is one of Earth’s greatest challenges, and given the oceans’ impact on climate, it is essential to consider the way in which teachers present information regarding the world’s oceans in their instruction. We conducted a threeday professional development (PD) workshop series with two cohorts. A total of 30 preservice and practicing K-8 teachers participated. We used a mixed-methods approach to measure changes in teachers’ knowledge and confidence in teaching about climate change and marine science in NGSS-aligned lessons as a result of the three-workshop PD experience Through pre and post workshop surveys we measured teachers’ knowledge of, and confidence in teaching, climate change and marine science, as well as their use of the NGSS. We conducted a focus group discussion with a subset of eight participants to elaborate on survey findings. We found that teachers’ knowledge and confidence in all three areas (marine science, climate change, and the NGSS) was statistically higher after the workshops than before. Additionally, teachers’ marine and climate science content knowledge also increased. The focus group discussion allowed for teachers to provide examples and context to support these quantitative differences. These findings suggest that our PD series and accompanying curricular materials are effective tools for addressing these interrelated problems.