<![CDATA[This study aimed to map students’ integrative thinking stages in solving integral problems presented in multiple representations. A Single Subject Research (SSR) using an A–B design was conducted involving three senior high school students categorized as high, moderate, and low ability. The students were selected purposively, and data were collected through task sheets, think-aloud protocols, and written responses across baseline and intervention phases. The intervention used adaptive integral worksheets based on four stages of integrative thinking: Articulate the Models, Examine the Models, Explore the Possibilities, and Assess the Prototypes. Data analysis combined visual plotting and qualitative interpretation. The results showed that moderate- and low-ability students improved significantly, with 100% non-overlapping data (PND), while the high-ability student showed stable performance with minor variations. Qualitative analysis revealed that high-ability students demonstrated advanced articulation but required additional cognitive challenges to sustain focus under time pressure. Meanwhile, moderate-- and low-ability students showed consistent progress across stages, especially when transitioning between representations. This research concludes that adaptive worksheets effectively enhance integrative thinking and support differentiated instructional design tailored to students’ representational reasoning. Keywords: Integrative thinking, Integral problem solving, Multiple representations, Single-subject research, Students’ thinking stages.]]>
