Joseph Assof is a high school and community college mathematics teacher and the math department chair at Health Sciences High and Middle College in San Diego, CA. He leads his department’s reform efforts to align to the Common Core Standards – with a focus on high quality instruction. He is a member of the San Diego County Math Leaders Task Force, whose mission is to support every student in meeting the rigorous expectations of the Common Core. Joseph co-authored Teaching Mathematics in the Visible Learning Classroom, High School, Teaching Mathematics in the Visible Learning Classroom, Grades 6-8, and The Teacher Clarity Playbook, and his classroom is featured in a number of Visible Learning for Mathematics, Grades K-12 videos.