Assess the ability to apply multilevel (hierarchical) modeling to evaluate instructional interventions using nested educational data: specify appropriate two- and three-level mixed-effects models, choose and justify fixed vs. random effects, model cross-level interactions, estimate and interpret ICCs and variance components, perform model comparison and diagnostics, handle clustering, missing data and small-cluster issues, and report substantive conclusions and implications for practice and policy (software-agnostic but reference to common tools allowed).