Prior work has shown that levels of self-reported student social-emotional learning (SEL) predict student achievement levels--as well as student achievement gains--but little has been done to understand if within-student changes in student reports of SEL are predictive of changes in theoretically related academic and behavioral outcomes. We use data from the California CORE Districts to examine whether changes in individual students' reports of their social-emotional skills from one school year to the next predict changes in state math and English language arts (ELA) test scores and attendance. We find that within-student changes in self-reported SEL predict changes in ELA achievement, math achievement, and attendance. These results are robust across model specifications and are stable across a wide variety of student subgroups.