Applied early adolescent researchers often sample students (Level 1) from within classrooms (Level 2) that are nested within schools (Level 3), resulting in data that requires multilevel modeling analysis to avoid Type 1 errors. Although several articles have been published to assist researchers with analyzing sample data nested at two levels, few articles are available to researchers seeking assistance with three-level data analyses. The purpose of this article is to extend the presentational logic and pedagogical flow employed in previous two-level pedagogical publications to illustrate the relevant issues researchers face, the decisions to be made, and the proper procedures needed, when analyzing cross-sectional three-level data. These procedures are demonstrated with a generated three-level data example based on the Early Childhood Longitudinal Study (ECLS-K) public use dataset. The generated data used in this article, as well as the SPSS, SAS, and Mplus model specification syntax files needed to reproduce all analyses in this article, and additional illustrative examples, are available as supplemental online materials at http://jea.sagepub.com/content/early/recent.