Less varied learning methods make learning activities boring. Emphasis on mastery of concepts and teacher dominance make students’ activities passive. The correct methods are needed to achieve the learning objectives. This study aims to evaluate the practicality of natural science learning devices for junior high school on the concept of environmental pollution using a problem-solving learning model. The research method uses Design Development Research by Tessmer. The data was taken at the small group evaluation and field test. Data were collected through observation of teacher and student activities with a scale of 1-4; self-assessment with a score of 1 (positive) and 0 (negative); and student response questionnaires on a scale of 1-5. The data were categorized and analysed descriptively. The results of the small group evaluation are: teacher activities get a good category; student activities with good categories in the preliminary and closing activities, but main activities are still quite good; self-assessment aspects show eight positive and two negatives, and student responses show nine positive and one negative. The field test results are: teacher and student activities get a “very good” category; self-assessment aspects show eight positive and two negative, and student responses are positive for all aspects.