Students often find it difficult to apply the order of operations (PEMDAS) even if they have already learned it in earlier grades. This is mainly because many rely too much on the mnemonic without fully understanding how it works, which can lead to confusion. As a result, students tend to make mistakes such as following the wrong order, misusing the left-to-right rule, or mixing up different operations. Because of these challenges, there is a need for a more engaging and meaningful way of teaching the concept. This study explored the effectiveness of the Sequential Problem Relay (SPR) strategy in improving the mastery of PEMDAS among Grade 11 students in Business Mathematics. Sequential Problem relay is a collaborative approach where students solve problems step by step while working together, discussing, and checking each other’s answers. A quasi-experimental design was used, involving two groups: one group used both SPR and the traditional method, while the other group used only the traditional method. The results showed that both groups started with similar knowledge based on the pretest. However, after the intervention, the experimental group performed better in the posttest. They showed improved accuracy and understanding, as well as active participation and peer learning. Although the difference in improvement between groups was small, the findings suggest that SPR can help reduce errors and improve students’ confidence and understanding in mathematics.