For elementary school students who are accustomed to solving single-layer mathematical problems, integrating multiple mathematical concepts and applying them to seek solutions is clearly a complex task. From the perspective of cognitive load, students may often find their intrinsic cognitive load exceeding their processing capacity when they face such tasks. This study investigated two strategies to manage intrinsic cognitive load: pretraining and segmented learning. The researcher first employed cognitive load theory to analyze the cognitive load faced by students using the two types of materials and then performed an experiment to verify theoretical analysis. At the same time, the researcher used the multidimensional cognitive load scale to gauge the cognitive loads perceived by the students. Experiment results showed that multidimensional cognitive load scale successfully measured the intrinsic load and extraneous load perceived by the students and pretraining resulted in lower perceived cognitive load than segmented learning. They further indicated that interaction effects exist between the two strategy groups and the high and low prior knowledge groups in posttest scores. This study suggests that pretraining is probably a more suitable instructional strategy to manage intrinsic load for most older elementary school students.