Abstract:
Understanding cell division requires students to interrelate multiple interacting biological entities across spatial and temporal scales. However, students often represent the process as a sequence of stages rather than as a coordinated system of interacting structures. This study examines how students structure their representations and explanations of cell division within an instructional sequence integrating kinesthetic enactment, yarn-based modelling, and paper-strip modelling across two design iterations using a Design-Based Research framework. Worksheet responses from 41 Grade 11 students across two iterations and 50 semi-structured interview episodes were analysed using a multidimensional coding framework capturing Embodied Mediation (EM), Representational Structure (RS), Explanation Form (EF), and Canonical Alignment (CA). Pre- and post-test scores showed substantial learning gains in both iterations (Iteration 1: Cohen's d = 1.60; Iteration 2: Cohen's d = 0.63, reflecting a ceiling effect). Structurally, student representations shifted from sequential stage-based organisation toward coordinated relational structures during modelling-intensive phases. Earlier integration of modelling in Iteration 2 produced markedly more coordinated representations at the meiosis phase (78.9% vs. 5.6% in Iteration 1). Explanatory reasoning stabilised at the dependency-based level across both iterations, with mechanism-based explanation remaining rare (6.4% of worksheet responses) and emerging only when representational scaffolding was combined with counterfactual probing. Embodied mediation supported representational coordination but did not independently generate mechanistic articulation — a dissociation that persisted across both datasets. These findings indicate that embodied pedagogy functions primarily as a structural scaffold rather than a direct route to causal understanding, and that bridging representational coordination to mechanistic explanation requires an additional layer of entity-level instructional scaffolding.
