Introduction: The objective assessment of motor skills in the school context is essential for analyzing and strengthening educational processes, considering that Fundamental Motor Skills (FMS) represent a core curricular component in the educational foundations of Physical Education. Objective: To evaluate the motor development of elementary school students and determine statistically significant differences through a pre- and post-test analysis. Methodology: Using a quantitative, non-experimental design, a total of n = 18 students were analyzed. The sample included n = 10 third-grade students and n = 8 fourth-grade students, with a mean age of 8.7 ± 0.90 years. The KTK test was used for motor assessment, and students participated in 18 juggling workshop sessions. Results: The motor assessments showed significant improvements, with the group's average score increasing from 3.78 to 4.72. Additionally, after the post-test, no students were classified as Problematic or Symptomatic, based on gender and individual performance analyses. Discussion: There is sufficient evidence supporting the positive effects of motor skill instruction in school-aged children. However, despite advances in educational policies, assessments of this dimension still face challenges in being effectively implemented. Conclusions: The results highlight not only the effectiveness of juggling as a strategy for developing fundamental motor skills but also propose a standardized and adaptable evaluation process, applicable to both summative and formative assessments in the teaching and learning context. This approach facilitates the identification of areas for improvement, focusing on each student's individual progress and development while addressing classroom diversity.