California's K-12 system relies on the Smarter Balanced Assessment Consortium (SBAC) English and mathematics tests to measure student academic progress and assess school and district performance. This report uses publicly available data to explore trends in student performance during the first three years this test has been in place. Key findings include: (1) In the 2016-17 school year, about 45 percent of 3rd grade students performed at proficient levels both in mathematics and English; (2) Overall, 2016-17 scores changed little from 2015-16; and (3) Scores for low-income students are consistently low across the state, while scores of higher-income students vary more widely by region. This report represents the third in a series on SBAC test scores in California (see Hill and Ugo 2016 and Ugo and Hill 2017). It has three sections. The first briefly describes the SBAC tests and the two ways they report student scores. The second section discusses 2016-17 results for major student groups, including low-income and English Learner (EL) students, and students with disabilities. The third section uses the SBAC data to examine growth in achievement from 2014-15 to 2016-17.