The primary goals of this research were to investigate the development of computational thinking (CT) skills among elementary students and to identify areas for improvement in their CT practices. Empirical investigations, accomplished in a learner-centered, problem-based learning curriculum for sixth-graders, sought to examine student proficiency in CT practices by analyzing programs developed by students. A total of 30 students participated in this study and eleven Scratch projects were analyzed. Results revealed that students showed high competence in Event, Parallelism, Sequence, and Design while low competence in Loop & Operator. Examination of the flow of their programs revealed how effectively students utilized CT concepts in CT practices. As areas for improvement, researchers identified an extremely fine-grained programming (EFGP) approach and a lack of abstraction.