Instructional materials are essential for teachers to support students in their
learning process. One type of instructional material that can engage students
effectively is augmented reality-based content. This research, a Research and
Development (RD) study, aims to develop augmented reality-based instructional
materials on the topic of angles and parallel lines. The study was conducted in class
7A of SMP Negeri 1 Purbalingga. The development model employed is the ADDIE
model, which consists of five stages: (1) Analysis, (2) Design, (3) Development, (4)
Implementation, and (5) Evaluation. Data collection methods included interviews,
questionnaires, and documentation. Data analysis utilized validation sheets
involving subject matter experts and media experts, teacher and student response
questionnaires, as well as assessments of student learning outcomes. The data
calculation involved determining the percentage of results from each validation
sheet and questionnaire, and calculating the N-Gain value derived from learning
outcomes. The results of the study indicate that: 1) The augmented reality-based
instructional materials on angles and parallel lines were deemed valid by both
subject matter experts and media experts. 2) The augmented reality-based
instructional materials on plane geometry received a percentage score of 90.38%
from teacher responses and 82.66% from overall student responses, with an
average overall percentage of 86.52%, classifying the materials as highly practical
and very good. 3) The instructional materials achieved an N-Gain score of 0.64,
indicating a moderate level of improvement, and thus can be considered effective.