This study explored the impact of the use of Khan Academy as an instructional and practical teaching material in primary and secondary school classrooms. The goal was to measure the platform’s effects on Chilean public school students’ performance in mathematics. We used blended learning methodologies consisting of a mixture of individual work and workshops guided by teachers according to the progress of each student. This process was supported by the Khan Academy and BA-Khan Academy platforms. The latter tool, BA-Khan Academy, facilitates teachers’ engagement with the blended learning process. Our analysis indicates that in the grade levels involved in the study, the students who received instruction with blended learning methodologies showed better results than control groups, both in mathematics assessments in class and on national standardized tests.