The complexity in the teaching and learning of mathematics were increased by several concerns in the education sector brought by the Corona Virus disease 2019 (COVID-19) pandemic. This pre-experimental research design with one-group pretest-posttest design examined the effectiveness of video lessons in improving the numeracy level of grade 7 students. The teacher-made video lessons used were validated and passed the evaluation of experts. The sample of this study was 37 grade 7 students of San Francisco National High School, Bulan, Sorsogon who were identified as non-numerates taken from the result of the numeracy test. The instruments used were the numeracy tool for grade 7 and 11 video lessons covering 28 most essential learning competencies. Based on the z-test result, the computed value of 7.67 is greater than the tabular value which is 1.96 (2-tailed) at 5% significance level. The result showed that there is a significant difference between the pre-test and posttest scores of the students. Moreover, the Cohen’s d effect size of 1.99 indicates that there is a large effect in the increase of test scores of the respondents. It implied that video lessons as a supplementary learning material to Learning Activity Sheets (LAS) improves the numeracy level of student. This study recommends the use of teacher-made video lesson as a supplementary learning material to the learning activity sheets in the distance learning modality of new normal education.