The study aimed to determine the effectiveness of the adoption of Project TEACH (TikTok as Educational and Comprehensive Hub) on increasing proficiency of Grade 11 Nela Yu Ferrer students in Principles of Marketing at Lumban Senior High School, Lumban, Laguna. The respondents were composed of 12 students of Grade 11 Nela Yu Ferrer under ABM strand. This research used descriptive-comparative method and utilized self-structured pre-test and post test to determine the effectiveness of the adoption of Project TEACH. Mean scores for pretest and post test were determined and t-test was used to analyze the significant difference between the pre-test and post-test. The t-value obtained was -12.52 and the critical value obtained was 2. 20 at 0.05 level of significance which indicate an increase in the proficiency of learners on Principles of Marketing through Project TEACH. The findings of this study indicated a significant difference between the result of the pre-test and post-test. Thus, the null hypothesis was rejected. The study had certain limitations as it was conducted during the Covid-19 pandemic. Based on the results presented on this study, the adoption of Project TEACH (TikTok as Educational and Comprehensive Hub) as contextuaized and localized learning material on Principles of Marketing for selected Grade 11 Nela Yu Ferrer students increased the learners proficiency.