Journal of Educational Science and Technology Volume 5 Number 2 August 2019 page 92-99 p-ISSN:2460-1497 and e-ISSN: 2477-3840 DOI: https://doi.org/10.26858/est.v5i2.8498 92 Improving The Students’ Cognitive Aspects In Oxy Acetylene Welding Course Bernardus Agus Munadi 1 , Sunaryo Soenarto 2 1 Mechanical Engineering, SMK Negeri I Sayegan, Indonesia Email: bagusmunadi@gmail.com 2 Technology and Vocational Education, Universitas Negeri Yogyakarta, Indonesia Email: sunaryos@uny.ac This is an open access article distributed under the Creative Commons Attribution License CC-BY-NC-4.0 ©2019 by author (https://creativecommons.org/licenses/by-nc/4.0/ ). ABSTRACT This study aims at improving learning activities and learning outcomes of cognitive aspects among X grade students of Metal Fabrication Engineering and Manufacturing, Vocational High School (VHS) using Problem-Based Learning (PBL) method. This study used classroom action research, which was conducted in two cycles. Each cycle consisted of four stages, i.e. planning, implementation, observation, and reflection. This study involved one collaborator to assist researchers in implementing PBL and to monitor the learning process. The data collection technique used observation method with checklist and rating scale instrument. The data were analyzed descriptively. The results showed that the PBL implementation method in ignition system learning improve the students’ learning activities with the percentage of 11.20%, the learning activities, in which 29 students were in very high category and 3 students with high category. Also, the learning outcomes of cognitive aspects getting higher to 5.32% consisting of remembering (86.87%), understanding (77.68%), applying (78.77%), analyzing (79.61%), evaluation (77.97%), and creating (79.16%) respectively. Moreover, the students’ learning outcomes raised of which 29 students (91.31%) achieved above the minimum completeness criteria. It means that the PBL model can be used by vocational high teachers as alternative learning process to improve their outcomes of the cognitive aspects. Keywords: problem-based learning; cognitive aspects; learning outcomes. INTRODUCTION The lack of education implementation in Vocational High Schools (VHS) has become a concern for the Indonesian government. The government keep trying to improve the quality of its learning process to achive the objectives of VHS education, i.e. to prepare students to enter the workforce in order to be able to compete in the current job market (Slamet, 2013). The subjects in VHS are divided into 3 groups, namely adaptive, normative and productive courses. According to Kurniasari, D., & Isnani (2015), the graduates from vocational school are expected to have competitiveness opportunity to enter the business world/industry and expected to be able to prepare ready-made workers in community life. However, the target of vocational education to achieve high scores and to realized qualified learning process is still far from the target of national education standards and vision of 2025. The learning process seems not reflected a clear concept and principles that result in the low material mastery among VHS students (Sanjaya, 2011). Based on the observation in SMK Negeri I Sayegan (Vocational High School I Sayegan), one of courses that is considered diffilcult and complex is oxy acetylene welding. Moreover, the given evaluation from the teacher in the form of a test appears less effective to help the students’ understanding, either the knowledge development or cognitive processes. In fact, most of students have been through their (Received: February-2019; Reviewed: April-2019; Accepted: June-2019; Published: August-2019)