Background and purpose: Many students experience difficulty engaging with abstract mathematical concepts such as ratio, often perceiving them as disconnected from meaningful activity. Connecting learning with purpose, curiosity, and the meaning of learning may help address this challenge. This study explores how a purpose-driven and culturally rich context can foster students’ engagement and enjoyment of learning, using ratio and enlargement as the mathematical content through which these experiences were examined. Aims: The aim was not primarily to measure improvement in computational understanding of ratio, but to explore whether students could enjoy engaging with ratio as an abstract concept, experience its usefulness through application, and participate actively in learning activities. Design or methodology: This case study involved about 30 Year 4 students (aged 9–10) in an elementary school. Four lessons were co-designed and delivered by teachers, graduate students, and university students. Students practiced enlarging figures on paper, then drew large-scale Nazca-style shapes in the schoolyard. Data were gathered from questionnaires (5-point scale and open responses), observations, student work, and reflections. Findings: Students rated the activities as very enjoyable (average 4.9/5) and showed strong enthusiasm and collaboration. Their reflections revealed curiosity, a sense of achievement, and increased engagement, suggesting that learning became more meaningful through participation in the activities. Conclusions, originality, value and implications: Purpose-driven, interdisciplinary lessons can support student motivation and promote deeper learning. This project demonstrates how integrating various themes can foster both understanding and engagement. It could be adapted to other subjects and grade levels to create opportunities for students to discover "why" they learn - through the process of learning itself.