JPII 10 (3) (2021) 447-461 Jurnal Pendidikan IPA Indonesia http://journal.unnes.ac.id/index.php/jpii THE EFFECT OF LEARNING BIOPHYSICS WITH STEM APPROACH ON SCIENCE PROCESS SKILLS AND CRITICAL THINKING: FIELD STUDY ON APPLICATION OF NA-AOGS FOR INCREASING SOYBEAN PRODUCTIVITY AND GROWTH RATE D. Rosana* 1 , N. Kadarisman 2 , A. Purwanto 3 , E. K. Sari 4 1 Department of Science Education, Universitas Negeri Yogyakarta, Indonesia 2,3 Department of Phyiscs, Universitas Negeri Yogyakarta, Indonesia 4 Department of Physics education, Universitas Negeri Yogyakarta, Indonesia DOI: 10.15294/jpii.v10i3.30695 Accepted: June 14 th 2021. Approved: September 28 th 2021. Published: September 30 th 2021 ABSTRACT Efforts to fulfill food security to anticipate population growth in Indonesia need to be supported by universities through research and community service. The application of the Natural Animal Audio Organic Growth System (NA-AOGS) with a STEM (Science, Technology, Engineering, and Mathematics) approach is an effort to help the community increase crop yields and accelerate the growth of soybeans (Glycine max (L.) Merill). The research method used is R&D (Research & Development). This model is a spiral cycle using five main activities as follows: (1) defining the product concept; (2) designing research products; (3) demonstrating the product in a limited trial; (4) developing the product through evaluating the test results; and (5) presenting the product to the public. The direct impact of learning is the improvement of science process skills and critical thinking of students in the Bio- physics course at the Natural Sciences Study Program, Universitas Negeri Yogyakarta. This impact is due to the effective application of STEM to link science learning with contextual technology and engineering (NA-AOGS), environmentally friendly technology (only using natural animal sound frequency variables), mathematical ele- ments in data analysis, and analysis of soybeans growth charts. The economic impact of this research is the sci- entific contribution in the form of adaptation of agricultural technology to increase soybean yields (an increase of 130.38% on an area of 2750 m 2 ). The novelty and contribution of this research is the integration of science learning with agricultural techniques and technology with a STEM approach to improve the welfare of farmers in educational institutions as a new model in science learning. © 2021 Science Education Study Program FMIPA UNNES Semarang Keywords: STEM; NA-AOGS; soybeans; critical thinking; science process skills *Correspondence Address E-mail: danrosana@uny.ac.id INTRODUCTION Significant changes occur in various fields due to the industrial revolution 4.0. These chan- ges also impact agriculture and education, imp- lying the need for changes in the science learning system at the primary, secondary, and higher edu- cation levels. The dominance of digital technolo- gy devices in the learning process, driven by the ongoing Covid-19 pandemic, has led to a high intensity of interaction between teachers and stu- dents using digital devices. For this reason, spe- cific skills are needed to anticipate global deve- lopments that require speed and accuracy of the information and the ability to solve increasingly complex problems. Mastery of the 4Cs (critical thinking, cre- ative problem solving, communication, and col- laboration) is required to meet the demands of mastering 21st-century skills. Therefore, in this research, Science Process-Skills (SP-Skills) and critical thinking (CT) have been developed. SP-