The Concepts in Cellular Biology professional development project is designed to equip middle grade and high school teachers with a greater understanding of science content and concepts associated with cellular biology. Participants actively experience and engage in reform-based methodologies of science teaching such as cooperative learning, the learning cycle, interdisciplinary learning, and alternative assessment, while exploring the following concepts: characteristics of living things and seed germination, cell structure and function, movement of substances into and out of cells, photosynthesis, cellular respiration, and enzymes/biological catalysts. With a focus on the understanding and use of process skills, as well as inquiry and its use in investigative procedures, the project enables teachers of life science to gain confidence in their ability to safely and effectively teach science through hands-on/minds-on experiences.