Dr. Osvaldo Soto has been active in mathematics education as a high school math teacher, mathematics education researcher and professional developer in San Diego for more than 20 years. He brings nearly two decades of secondary teaching experience and over a decade of research-based professional development experience. Dr. Soto is interested in the development of secondary teachers’ proof schemes and how teachers draw on their proof schemes to guide instruction. Dr. Soto wears many hats. Currently he is the director of the Discrete Math Project, the UC San Diego Math Project and Math for America San Diego. Housed primarily at UC San Diego’s Center for Research On Educational Equity, Assessment & Teaching Excellence (CREATE), but also at San Diego State University’s Center for Research in Math and Science Education, Dr. Soto works with a variety of K-12 personnel and University faculty to address pressing issues in mathematics education. Through his work at CREATE he serves as a member of the CREATE STEM Success Initiative, a collective effort linking UC San Diego faculty, staff and students to the San Diego education community to support K-20 STEM education in our region.