In California, the typical college-prep course sequence in math includes Algebra I, Geometry, and Algebra II. Students advance through these courses at different rates. A number of students proceed at a quick pace, with some completing Algebra II by the end of 10th grade and a few even earlier. At the other end of the spectrum, some students struggle with 7th grade math content and/or Algebra I for years. The largest portion falls somewhere in the middle. A better understanding of students' trajectories through college-prep math courses in high school can help state leaders and local K-14 educators identify potential leverage points for improving students' prospects in math and STEM courses and careers after high school. This brief finds that California students get through college-prep math at different paces; few students test as ready for college-level math at the end of 11th grade; California Standards Test (CST) data can help clarify priorities for improving students' math performance; and districts have access to student-level data that can provide local answers to some vital questions. 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: The Grade 7 Pivot Point. Issue Brief" (ED606336).]