<![CDATA[This study addresses the need for behavior-oriented instructional design in Islamic higher education by developing the Halal Behavior Instructional Model (HBIM), which integrates the Theory of Planned Behavior (TPB) and constructivist pedagogy to support halal behavior among university students. The study employed a Research and Development (R&D) approach guided by Backward Design. The development process included needs analysis, instructional design, product development, expert validation, revision, and limited classroom implementation. The HBIM connects TPB components with constructivist strategies by linking attitude with value exploration, subjective norm with social dialogue, perceived behavioral control with experiential learning and problem-solving, and behavioral intention with reflection and action planning. The study involved 133 undergraduate students in a one-group pretest–posttest effectiveness test and 115 students in the response evaluation. Expert validation showed that the developed teaching materials were very feasible in terms of content, instructional design, and language. Student responses were also very positive, with an overall mean score of 4.59. The effectiveness test showed a statistically significant improvement in students’ halal behavior, with the mean score increasing from 37.34 in the pretest to 38.71 in the posttest, t(132) = 2.208, p = 0.029. However, the small effect size (Cohen’s dz = 0.19) and low N-Gain score (0.18) indicate that the magnitude of behavioral change remained limited. These findings suggest that HBIM can initiate halal behavior formation through contextual cases, discussion, reflection, self-evaluation, and action planning, although sustained reinforcement is needed to strengthen long-term behavioral consistency.]]>
