Improving Students' Conceptual Knowledge in Online Distance Learning through the Use of Micro-Lectures: A Photosynthesis Example

The shift to online distance learning due to the COVID-19 pandemic presented a challenge to develop instructional materials that could compensate for the limitations of the prevailing learning modality. Micro-lectures are short instructor-made videos that are meant to deliver lessons in ways that do not overwhelm the learners' working memory in understanding conceptually challenging topics such as photosynthesis. This action research used a Quasi-experimental mixed-method approach through micro-lectures in teaching photosynthesis to an intact group of 60 grade 12 STEM students. The instruments and methods used were pre-test and post-test, survey forms, journal entries, and focus group discussions. The results showed that watching micro-lectures positively affected students' test performance and knowledge gain in the different concepts in photosynthesis. Students view micro-lectures as an effective learning material appropriate for online learning due to their ability to declutter and segment the lessons, enhance engagement levels, provide a sense of teacher presence, and encourage flexible learning.