Purpose: Due to the importance of descriptive evaluation in elementary school, the present study was conducted with the aim of designing and validating of academic achievement evaluation pattern in elementary schools Multi-Grade Classes. Methodology: The present study in terms of time was cross-sectional, in terms of purpose was applied and in terms of implementation method was qualitative. The research population was university experts and managers primary education staff of country in 2021 year. The research sample was 15 people according to the theoretical saturation principle who after examining the inclusion criteria were selected by purposive sampling method. The research tool was a semi-structured interview and data were analyzed by coding method in MAXQDA software. Findings: Findings showed that the academic achievement evaluation pattern in elementary schools Multi-Grade Classes has 306 indicators and 41 components in 6 categories of goals and approaches (with 11 components such as comprehensive evaluation and its application to life, descriptive evaluation in all areas, descriptive evaluation qualification with reported structure change and process-based qualitative evaluation with structuralist approach), contextual (with 4 components of management equipment implementation of evaluation of Multi-Grade Classes, rationalization of executive infrastructures with emphasis on reducing density in Multi-Grade Classes, quality of teaching and teacher evaluation methods and culture and dissemination of descriptive evaluation factors), input (with 5 components of qualitative evaluation tools, paying attention to the educational expectations of Multi-Grade Classes, performing descriptive evaluation in all teaching stages, adaptation of Multi-Grade curriculum with descriptive evaluation and coordination of weekly program with learning roadmap), process (with 13 components such as increasing confidence, calmness, satisfaction and self-esteem, reducing the anxiety of Multi-level students, quality of criteria in the report card, variety of self-assessment and peer assessment and parenting assessment tools and emphasizing to group learning of Multi-Grade students), output (with 5 components of participatory decision making for basic promotion, quality of reporting and report card of student, validity, reliability and testability of Multi-level descriptive evaluation, continuous learning with diverse feedback and Multi-dimensional quality the descriptive evaluation with qualitative feedback) and outcome (with 3 components of annual analysis of the findings of descriptive evaluation, analysis of the findings of descriptive evaluation longitudinally and analysis of the consequences of descriptive evaluation). Also, the content validity ratio of 0. 90 and the content validity index of 0. 92 according to the experts' opinion indicated the appropriate validity of the academic achievement evaluation pattern in elementary schools Multi-Grade Classes. Conclusion: According to the results of this study, planning is necessary to the academic achievement evaluation pattern in elementary schools Multi-Grade Classes.