<![CDATA[This study aimed to describe the improvement of the learning process and mathematics learning outcomes through the implementation of the Guided Discovery Learning model assisted by three-dimensional geometric media among fifth-grade students at SDN 104/II Sungai Pinang. The study was motivated by the low level of student engagement and mathematics learning outcomes, particularly in understanding three-dimensional geometric concepts. The initial data showed that only 2 out of 30 students (6.67%) achieved the established Learning Objective Mastery Criteria (KKTP) of 70, while 28 students (93.33%) did not achieve the criteria, with a class average of 34.08. This study employed Classroom Action Research conducted in two cycles, with each cycle consisting of planning, action, observation, and reflection stages. The subjects were 30 fifth-grade students. Data were collected through observation sheets of teacher and student activities and mathematics achievement tests. The results showed an improvement in the learning process after the implementation of Guided Discovery Learning assisted by three-dimensional geometric media. Student activity in the good and very good categories increased from 53.3% in Cycle I Meeting 1 to 66.7% in Cycle I Meeting 2, then increased to 80.0% in Cycle II Meeting 1 and 88.0% in Cycle II Meeting 2. Mathematics learning outcomes also improved, with the percentage of students achieving the KKTP increasing from 60% in Cycle I to 100% in Cycle II among the 25 students who participated in the Cycle II test. When calculated based on the total 30 students, the classical mastery level reached 83.33%. These findings indicate that the Guided Discovery Learning model assisted by three-dimensional geometric media can improve the learning process and mathematics learning outcomes of fifth-grade students at SDN 104/II Sungai Pinang.]]>
