The study was primarily concerned with the effect of Worktext as supplemental materials in improving mathematics? performance of grade 9 students from three schools; Sto. Tomas Integrated High School (STIHS), Dayap National Integrated High School (DNIHS) and Santa Cruz Integrated National High School (SCINHS). The researcher identified the following: the level of perception of learners from three schools to the supplemental worktext in terms of objective, content and activity; the level of student?s attitude in distance learning using the supplemental worktext in terms of self-learning and time-management; the level of Math performance of learners from three schools with and without the use of supplemental worktext. The researcher also determined the difference in the Mathematics performance of learners from three schools with and without the use of supplemental worktext and the perception of learners to the supplemental worktext elements and their attitude towards distance learning significantly relates to their Mathematics performance upon using the supplemental worktext. Based on the summary of findings mentioned shows that worktext as supplemental material has a significant effect to the performance of the students. The significant relationship of the content of worktext and attitudes has no significant relationship with the performance of students. It was recommended that Mathematics Teachers may also develop and design their supplementary materials for their students which they think would be of great help for their students to develop and enhance their mathematics performance. It is also recommended to ask students about their perceptions of the materials to be implemented; this will greatly assist teachers in considering their attitudes when developing a material.