The goal of the current research was to develop the levels of depth of scientific knowledge and Reducing the Cognitive Load among primary school students,To achieve the goal, a proposed strategy was used based on the integration of the cognitive apprenticeship and Thomas and Robinson strategies, Accordingly, a research group was selected consisting of (76) male and female students in the fifth grade of primary school - second semester of the academic year 2023-2024 AD, and the two research tools were (levels of depth of scientific knowledge Test, And the cognitive Load scale), and the research used the experimental method based on the semi-experimental design with the control and experimental groups, where the two research tools were applied beforehand, then the proposed strategy was used in teaching to the experimental group and the usual strategy for the control group, and after completion, the two research tools were applied later, and the results reached The students in the experimental group excelled in the post-application compared to the control group, Also the experimental group excelled in the post-application compared the pre-application with statistically significant differences at the level of (0.01) in the levels of depth of scientific knowledge as a whole and at each level separately,Their cognitive Load was also reduced, and the research presented its recommendations and proposals in light of the results reached.