Abstract
Science process skills are an indispensable ability in studying science because they are positively correlated with student science learning outcomes. The development of science process skills in junior high school students can be facilitated through the application of teaching materials based on guided inquiry learning. The purpose of this study was to develop science teaching materials on appropriate biology materials using a guided inquiry model to improve the science process skills of junior high school students. The development of teaching materials is carried out through the application of the 4 D development model which is focused on the Define, Design and Develop stages. The teaching materials developed are in the form of teaching materials and students' worksheet which emphasize the application of science process skills and concept map preparation. The feasibility test of teaching materials was carried out by three experts consisting of material experts and junior high school science teachers. The feasibility test is also equipped with student assessment of the teaching materials being developed. The instrument for the feasibility test is in the form of a questionnaire with a score based on a Likert scale of 1-4. There are three indicators for the assessment of teaching materials including presentation, content, and language. The results showed the average score for the assessment of teaching materials from experts on indicators of content, presentation, and language, respectively 87%, 84%, and 85.5% with an average of 85%, while students gave an average feasibility score. by 80%. The conclusion of the study is that the teaching materials developed are very suitable to be used to support the improvement of science process skills of junior high school students.