Higher Order Thinking Skills (HOTS) are crucial for 21st-century learning and global competitiveness. While Malaysia emphasizes HOTS in its education blueprint, student performance in international assessments like TIMSS and PISA remains low, particularly in geometry, specifically Isometrical Transformation. This study aimed to address this by developing and evaluating a technology-based Flipped Classroom Learning Strategy (FCLS) to enhance students' HOTS in Isometrical Transformation. The low performance is attributed to conventional teaching methods, teachers' struggles with effective HOTS pedagogy, and students' difficulty connecting mathematical concepts to real-life situations. Existing studies focusing on HOTS improvement often neglect Isometrical Transformation. Therefore, this research investigates the potential of FCLS to improve students' understanding and application of HOTS in this specific area of mathematics.

The literature review highlights the importance of HOTS in education and its current low levels in Malaysian students, particularly in geometry. It discusses Bloom's Taxonomy and its revisions, emphasizing the significance of critical thinking skills. The review examines the challenges faced by Malaysian students in understanding Isometrical Transformation, including difficulties with specific concepts (translation, reflection, rotation), connecting concepts to real-life applications, and answering HOTS-focused questions. The under-exploration of FCLS in mathematics education, especially at the secondary level, is also emphasized. The review also identifies the lack of detailed implementation guidelines for FCLS activities and the absence of studies specifically focused on its impact on HOTS in Isometrical Transformation at the secondary school level. The study builds on this gap by proposing a comprehensive FCLS approach with detailed activity guidelines.

This study employed a two-stage methodology. Stage 1 focused on the design and development of FCLS activities for Isometrical Transformation, guided by the ADDIE model. This involved three phases: (1) needs analysis (identifying student learning difficulties in each level of HOTS), (2) design and development of FCLS activities (both in-class and out-of-class activities aligned with the Isometric Transformation topic), and (3) evaluation (content validation by 11 experts). Stage 2 used a quasi-experimental design to evaluate the effectiveness of the developed FCLS activities. 131 Form 2 students from two secondary schools in Johor were divided into treatment (FCLS) and control (conventional teaching) groups. Data collection involved a pre-test and post-test measuring HOTS in Isometrical Transformation. The pre-test assessed students' initial HOTS abilities before any intervention. After eight weeks of intervention, a post-test was administered to evaluate the impact of the FCLS. The pre-and post-tests were composed of subjective items assessing applying, analyzing, evaluating, and creating skills. The Rasch model was used to assess the reliability, item fit, and unidimensionality of the HOTS test items. The Mann-Whitney U test was used to compare pre-test scores between the control and treatment groups. The Wilcoxon signed-rank test was used to compare pre- and post-test scores within each group. Finally, the Mann-Whitney U test was used to compare post-test scores between the control and treatment groups.

The study found no significant difference in pre-test HOTS scores between the treatment and control groups, indicating that the groups were comparable before the intervention. However, significant differences (p = .000 < .05) emerged in the post-test. The FCLS group showed significant improvement across all four HOTS levels (applying, analyzing, evaluating, and creating), compared to the control group. This suggests that the FCLS activities were effective in improving students' higher-order thinking skills. The Rasch analysis showed high reliability and acceptable item fit for most items, validating the instrument's use in the study. Unidimensionality was partially achieved, with minor adjustments suggested based on the analysis. The Mann-Whitney test revealed significant differences in post-test scores between the control and treatment groups, with the FCLS group performing substantially better across all four HOTS levels and in the overall HOTS score. The Wilcoxon test indicated significant improvements within the treatment group for all HOTS levels, further supporting the effectiveness of FCLS. The significant differences found highlight the positive impact of FCLS in fostering different levels of HOTS in the topic of isometric transformation.

The findings support the hypothesis that FCLS enhances students' HOTS in Isometrical Transformation. The significant improvements in the treatment group across all HOTS levels demonstrate the effectiveness of the designed activities and their alignment with the principles of Social Constructivism. The integration of technology and in-class and out-of-class activities fostered a dynamic and interactive learning environment that encouraged collaborative learning and critical thinking. Specific activities, such as using games related to daily life, group discussions, and project-based learning, contributed to improved performance at different HOTS levels. The results align with previous research emphasizing the benefits of FCLS in enhancing student engagement and achievement in mathematics. The study's success highlights the potential of using technology-integrated FCLS to improve HOTS in mathematics teaching in Malaysia.

This study successfully developed and validated technology-based FCLS activities for enhancing students' HOTS in Isometrical Transformation. The findings strongly support the effectiveness of this approach, demonstrating significant improvements in HOTS across all four levels in the treatment group compared to the control group. This suggests that FCLS can be a valuable tool for mathematics educators seeking to improve students' critical thinking abilities. Future research could explore the long-term effects of FCLS, investigate its applicability to other mathematical topics, and examine the role of teacher training in successful FCLS implementation. Examining the impact of different technology tools within FCLS could also offer valuable insights.

The study's quasi-experimental design, while providing valuable insights, is subject to certain limitations. The use of non-equivalent groups from different schools might introduce extraneous variables. Although efforts were made to control potential confounding factors by matching the groups based on relevant characteristics, these variables may still affect the results. The relatively short duration of the intervention (eight weeks) may not allow for a comprehensive evaluation of the long-term effects of FCLS. Future research employing randomized controlled trials and longer-term assessments would strengthen the generalizability of the findings.