Background <p>The increasing global burden of chronic diseases, disability, and population aging highlights the growing need for well-prepared rehabilitation professionals. Educational experiences play an important role in shaping students’ perceived knowledge, attitudes, and motivation, which are key components of professional development. In Iran, many students enter rehabilitation programs with limited prior exposure to the field. This study aimed to evaluate the effect of the Principles of Rehabilitation course on undergraduate students’ perceived knowledge, attitude, and motivation, and to explore differences associated with early clinical exposure.</p> Methods <p>A quasi-experimental pretest–posttest design was conducted among 184 undergraduate students in physiotherapy, occupational therapy, speech therapy, and audiology at Tabriz University of Medical Sciences. First-year students (<i>n</i> = 107) completed the Rehabilitation Sciences Knowledge, Attitude, and Motivation (RS-KAM) questionnaire before and after the course. Physiotherapy students who had not yet taken the course served as the control group. Third-year students (<i>n</i> = 77) completed a single assessment for cross-sectional comparison. The primary analysis compared change scores between intervention and control groups. Secondary analyses included within-group comparisons, cross-sectional analyses, and correlation assessments.</p> Results <p>Between-group analysis showed a significant difference in attitude change, with the intervention group demonstrating a more positive shift compared with the control group (<i>p</i> = 0.001). No significant between-group differences were observed for perceived knowledge or motivation. In both groups, perceived knowledge increased over time, while motivation decreased. Cross-sectional comparisons indicated that third-year students reported higher perceived knowledge but lower motivation than first-year students. Positive correlations among perceived knowledge, attitude, and motivation were observed, particularly among first-year students.</p> Conclusions <p>The <i>Principles of Rehabilitation</i> course was associated with improved student attitudes but did not result in greater gains in perceived knowledge or motivation compared with controls. These findings suggest that structured educational experiences may contribute to the development of professional attitudes, while perceived knowledge may be influenced by both formal and informal learning experiences. The observed decline in motivation highlights the importance of educational strategies that support students’ motivation alongside their academic and professional development.</p>