Teacher churning likely harms student achievement. However, the phenomenon of within-school grade-level teacher reassignments is understudied. The current study provides descriptive evidence on the frequency and predictors of within-school teacher grade switching using both longitudinal administrative data from Michigan and nationally representative survey data. About 7% of self-contained classroom teachers change grades following any given school year. Inexperienced teachers are relatively more likely to switch grades, and grade-level reassignments are inequitably distributed across both schools and students. For example, urban schools experience significantly higher rates of grade switching. Charter schools experience significantly less grade switching than traditional public schools.