Checkley, K. (2008). The essentials of social studies, grades K-8: Effective curriculum, instruction, and assessment. Association for Supervision and Curriculum Development.
Chicago Style (17th ed.) ZitazioaCheckley, Kathy. The Essentials of Social Studies, Grades K-8: Effective Curriculum, Instruction, and Assessment. Alexandria, Va.: Association for Supervision and Curriculum Development, 2008.
MLA (9th ed.) ZitazioaCheckley, Kathy. The Essentials of Social Studies, Grades K-8: Effective Curriculum, Instruction, and Assessment. Association for Supervision and Curriculum Development, 2008.
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