Artificial photosynthesis is a promising approach to generate important commodity chemicals using abundant chemical feedstocks and renewable energy sources. Despite its importance, affordable and effective hands-on classroom activities that demonstrate artificial photosynthesis and teach key concepts, especially for primary school students, is lacking. This will be a critical step in the development of the next-generation energy workforce, especially one that is diverse in race and gender. To aid in this effort, we present an artificial photosynthesis lesson plan based on active-learning techniques that uses safe and highly accessible materials (baking soda, tap water, plastic jars, Ni coil, alligator clips, and a solar cell) to perform solar-powered water splitting. The efficacy of the lesson plan in teaching basic concepts of artificial photosynthesis was evaluated with pre- and post-test data, which shows a statistically significant improvement in overall student understanding. Importantly, the data show that the lesson plan presented here is effective at narrowing the performance gap between minority students and overly represented groups. This study aids in the development and education of a demographically diverse energy workforce through an active learning-based lesson plan for primary school students.