This research aims to show the effect of the pictorial puzzles strategy on developing expressive performance and reflective thinking among fifth-grade scientific students in composition. The researchers adopted the experimental design with partial control for the experimental and control groups of pre and post tests. Two hypotheses were formulated and tested. The research sample consisted of (80) students of the fifth grade scientific in Hawija Preparatory School for Boys, in Kirkuk governorate for the academic year 2019-2020. They were distributed randomly and equally into two equal groups. To achieve the aims of the research three research tools are required: The first pictorial puzzles, as the researchers prepared (8) images in the form of puzzles that are studied in expressive performance. The researchers made sure of their validity. The second was a criterion for correction with (8) items which were valid and consistent. The third is a measure of contemplative thinking consisting of (35) items divided into (4) dimensions followed by five alternatives. Their validity, stability and distinguishability of its items were approved. Following the completion of the experiment, the two research tools were used to analyze the two research groups. When that data are collected, analyzed and treated statistically using the SPSS statistical program, the following result was revealed. There is a statistically significant difference between the mean scores of the two research groups in the development of expressive performance and reflective thinking in favor of the experimental group. Accordingly, a number of conclusions emerged.