This study aims to produce a syntax model and EdPuzzle-based blended learning device that is valid, active and effective to improve students' thinking skills in engineering mechanics. Including research and development (Research and Development), discusses the ADDIE development model, including Analysis, Design, Development, Implementation, Evaluation. Edpuzzle-based blended learning testing model in learning and critical thinking skills test of students is done in class X students of SMK Negeri 5 Surakarta. The trial design of this study used One Group Pretest-Posttest Design. The results showed that the average value of the RPP learning instrument worth 87.6%, with very decent criteria, the value of the material worth of 80.8 with a very decent category, the value of the media instrument of 84.2% with a very decent category. Meanwhile, 86.5% with very decent criteria. The use of EdPuzzle-based blended learning models in limited trials of teachers and students get an average value of 82, 90% with very practical category. Thus the EdPuzzle-based blended learning model is effective in improving students 'thinking skills indifference with the students' critical test results from 70 to 89. The results of this study indicate that the EdPuzzle-based blended learning model developed is following the correct, practical and effective.