Reed Mat Weaving Helps Rural Colombian Students Connect Culture and Geometry

The unit, built around the local craft of weaving esterillas, or reed mats, was designed to test whether the mathematical knowledge embedded in a traditional artisanal practice could serve as a genuine bridge into formal school geometry and measurement. The study, published in Discover Education, reports that the approach produced strikingly uneven but often impressive results: most students grasped why non-standard units fail, a third reached formal area reasoning usually taught in later grades, and nearly all excelled at strategic problem-solving rooted in the artisans’ real economic constraints.

The research followed a qualitative action research model and was organized in two interconnected phases derived from an ethnomathematical framework. In the first, ethnographic phase, researchers worked with three highly experienced artisans from the Párate Bien community who volunteered to share their knowledge. Using semi-structured interviews, participant observation, audiovisual recording and a field diary, the team documented the mathematical practices woven into the craft: the body-based measurement units known as cuarta, jeme, deo and puño, the rectangular and trapezoidal shapes of different mat types, and the sequential decision-making behind choosing dimensions for mats intended for horses, donkeys, mules or buffalo. The researchers deliberately did not impose metric measurement during the craft activity itself, and metric equivalences were established collaboratively, with artisans measuring their own body units on a tape and explaining how the values varied from person to person.

The ethnographic documentation revealed a coherent, specialized knowledge system rather than an informal approximation of academic mathematics. Artisans’ spontaneous drawings served as primary sources: one sketch of the weaving loom combined metric dimensions, two meters tall and one meter wide, with internal spacings specified as four handspans, while other drawings laid out the dimensions of the Esterilla Caballo, a trapezoidal mat whose edges were given in spans, fingers and fists, and the rectangular Esterilla Burro. The researchers described this translation work as ethno-modeling, an attempt to mobilize the mathematical structures of the craft pedagogically without reducing artisanal knowledge to a mere pretext for introducing predetermined curriculum content.

The second phase transformed this documentation into a didactic unit titled The Mathematics of the Reed Mat, implemented at IED Euclides Lizarazo with the nine fifth-graders. The unit comprised four sessions. Task 1 asked students to articulate the artisan’s step-by-step decision logic before any formal geometric terminology was introduced. Task 2 confronted them with a cognitive conflict: measuring the same object with their own body units produced divergent results, which was used to motivate the need for a standardized metric system and proportionality-based unit conversion. Task 3 required students to determine which mat occupied the most surface area, representing rectangles and trapezoids to scale and comparing areas by tiling or by formula. Task 4 posed the artisan’s challenge, an ill-structured problem involving uncertainty about material yield and a pending order of thirty mats.

The theoretical lenses for interpreting the outcomes were the Van Hiele hierarchy of geometric thinking, which runs from holistic visualization through empirical analysis to informal deduction and formal proof, and Duval’s theory of semiotic representation registers, which holds that genuine mathematical understanding lies in coordinating and converting between registers such as physical objects, drawings, language and symbols. The unit was deliberately sequenced so that students had to move between the physical mat, artisanal drawings, bodily units, scale drawings and formulas, with conversions between registers expected to be the principal locus of difficulty.

The results confirmed that prediction with unusual clarity. In Task 2, seven of the nine students conceptually understood why their handspan measurements differed, correctly attributing the variability to individual body size, yet only three students successfully executed the two-step conversion algorithm translating body-based measurements into metric units. The researchers interpreted this conceptual-procedural gap not as a failure of metric understanding but as a typical conversion difficulty between semiotic registers, arguing that the cultural context supplied the why compellingly while the how of formal calculation still requires targeted instructional support.

Geometric reasoning in Task 3 spread across the Van Hiele hierarchy within a single classroom. Two students remained at Level 0, justifying their answers perceptually, for example arguing that the buffalo mat was bigger because it used more reed, even though their conclusions were correct. Three students advanced to Level 1, employing tiling strategies that treated area as a quantity covered by unit squares. Most notably, three students reached Level 2, informal deduction, mobilizing area formulas including the trapezoid formula for the non-rectangular Esterilla Caballo, a calculation typically introduced in higher grades. The researchers attributed this accelerated performance to the semiotic richness of the task: students who had already coordinated the physical, figural and verbal registers of the mat arrived at the symbolic register with conceptual scaffolding in place.

Task 4 elicited the strongest and most uniform performance, with seven of nine students rated outstanding. Facing uncertainty about material and time, students spontaneously analyzed best-case and worst-case scenarios, proposed relying on community networks to obtain extra reed or ready-made mats, and optimized plans for time efficiency. One representative solution combined harvesting additional reed with purchasing part of the material, estimating that around twelve mats could be produced toward the order of thirty. The authors described this as evidence of artisanal rationality, a practical mode of reasoning that balances material, labor, time and social constraints rather than seeking a single mathematically optimal answer, and argued that the authentic economic framing activated tacit cultural knowledge that decontextualized exercises leave dormant.

Taken together, the findings support the two-phase ethnomathematical approach as a viable framework for core mathematics instruction rather than a decorative supplement. The intervention maintained high cognitive demand, evidenced by engagement with formal geometric concepts and formulas, while grounding abstraction in lived practice and validating students’ cultural identities. The heterogeneity of outcomes, the authors argue, reflects the diverse pathways through which learners construct mathematical knowledge and points to the need for differentiated instruction even within culturally grounded pedagogies.

The authors are explicit that these conclusions carry heavy qualifications. The sample of nine students at a single school limits generalizability, the study captures a snapshot at one point in time without a control group or longitudinal follow-up, and affective dimensions such as motivation, mathematical identity and cultural pride, though central to the ethnomathematical project, were not formally assessed. Whether students who build strong conceptual foundations through cultural contexts eventually close the procedural gap in unit conversion remains an open question. The researchers call for multi-site replications with larger samples, quasi-experimental designs comparing ethnomathematical and conventional instruction, and longitudinal tracking, while noting that the study offers a replicable model for educators seeking to treat local practices as primary mathematical content rather than marginal enrichment.

Subject of Research: An ethnomathematical teaching unit based on reed mat weaving was evaluated for its effects on metric and geometric thinking among rural Colombian fifth-grade students.

Article Title: Bridging local craftsmanship and formal geometry in a rural Colombian classroom

Article References: Casalin, J. M., Peña-González, D., & Torres-Peña, R. (2026). Bridging local craftsmanship and formal geometry in a rural Colombian classroom. Discover Education, 5(1), Article 1216. https://doi.org/10.1007/s44217-026-02300-4

Image Credits: AI Generated

DOI: 10.1007/s44217-026-02300-4

Keywords: ethnomathematics, mathematics education, geometry, measurement, rural education, Colombia, artisanal knowledge, Van Hiele levels, action research, primary school, cultural heritage, didactic unit