<![CDATA[The shift to online learning created a distinct challenge in training students' higher-order thinking skills (HOTS), given that vocational competencies have long relied on direct face-to-face interaction. This study examined how far the use of social media in learning (WhatsApp feedback and Google Meet (G-Meet) synchronous sessions) applied through the Small Group Discussion method, contributed to the higher-order thinking skills of students in the Basic Mechanical Engineering Design (Dasar Perancangan Teknik Mesin, DPTM) course. A quantitative experimental design with a pretest-posttest format was used across two groups: experimental class 1 received WhatsApp feedback, while experimental class 2 received G-Meet synchronous sessions. Data were gathered through a HOTS test instrument and a student response questionnaire, then analyzed with an independent samples t-test once the normality and homogeneity assumptions were satisfied. The posttest mean for experimental class 1 reached 68 (gain score 47), while experimental class 2 reached 79 (gain score 66.14). The hypothesis test produced a significance value below 0.05, confirming a significant difference between the two treatments; G-Meet synchronous learning proved superior to WhatsApp feedback in raising students' higher-order thinking skills. These findings offer vocational teachers empirical guidance for choosing and designing social-media-based Small Group Discussion strategies that most effectively cultivate higher-order thinking skills under limited-bandwidth, post-pandemic conditions, and contribute new comparative evidence on the instructional value of synchronous versus asynchronous social media use for technical and vocational education. ]]>
