The end of 7th grade provides an important moment to assess how prepared California's students are to succeed in the more advanced math curriculum that starts with algebra. At a minimum, all California students are required to successfully pass Algebra I in order to receive a high school diploma. But Algebra I also functions as the gateway to more advanced math and science coursework. Where students stand at the end of 7th grade determines how quickly and successfully they get through that gateway. That makes 7th grade math an important "pivot point" in the K-12 math pipeline. This brief finds that a growing number of 7th graders meet the state's expectations, but math achievement varies dramatically based on student ethnicity; mastery of 7th grade math concepts is a meaningful indicator of algebra readiness; the lowest-achieving 7th graders are much less likely to pass the math section of the California High School Exit Examination (CAHSEE) before high school graduation; and students' later prospects in math pivot on their success through 7th grade. If California is going to increase the number of students who can succeed in sophisticated math and science courses in high school--and effectively pursue STEM degrees and careers after graduation--it must improve and accelerate many students' mathematical skills and understanding through 7th grade. This brief is one of three on K-12 student achievement in mathematics for educators and policymakers wanting to strengthen science, technology, engineering, and mathematics (STEM) education in California. [This brief was prepared with input and advice from the California STEM Learning Network (CSLNet). For the other briefs in this series, see "California's Math Pipeline: Success Begins Early. Issue Brief" (ED606334) and "California's Math Pipeline: Many Routes through and around College-Prep Courses. Issue Brief" (ED606366).]