This study developed and validated the CODE Instructional Approach (Case-Organized, Dramatized, and

A total of twelve (12) third-year BSED Science students enrolled in PHSc108 Biochemistry participated in the

implementation phase of the study. Using the ADDIE instructional design model, the Analysis Phase revealed

several learning needs, such as students' persistent misunderstandings, difficulty visualizing molecular processes,

and a strong preference for visual and hands-on learning strategies. A panel of seven qualified evaluators assessed

the instructional materials for validity, clarity, and pedagogical integrity. The overall validity rating for the

pretest–posttest instrument was 3.77, and the rating for the Teaching Guide was 3.70, both interpreted as “very

understanding by integrating multimodal, contextualized, and embodied learning activities.

Multimodal Instruction

The Central Dogma of Molecular Biology explains how genetic information moves from DNA to RNA to protein,

and it is considered a foundational concept in biology education. For preservice science teachers, understanding

the Central Dogma is essential because it supports learning in genetics, biochemistry, cell and molecular biology,

and related fields. Since this concept plays a central role in the curriculum, students need instructional approaches

that help them build accurate and coherent mental models of molecular processes.

Despite its importance, the Central Dogma is consistently identified as one of the most challenging topics for

difficulties have been observed in local classroom contexts, where many students rely heavily on memorization

and find it difficult to construct meaningful mental models of molecular events. The diagnostic findings in this

study reflected the same pattern of fragmented understanding and persistent misconceptions, which suggests that

lecture-based teaching may not sufficiently promote conceptual learning.

In response to these difficulties, a variety of innovations in molecular biology instruction have emerged.

Simulation-based and virtual learning tools have been shown to help students visualize abstract molecular

interactions that cannot be observed directly (Cano, 2022; Park and Lee, 2024). Contextualized instruction

enables learners to relate gene expression concepts to real-world scenarios, while inquiry-based laboratory

activities such as GFP plasmid expression provide firsthand experience with transcription and translation

(Bujanda and Anderson, n.d.). Other multimodal approaches, including manipulatives, model construction, art-

based learning, without combining these methods into an integrated framework. Only a few studies have

attempted to unify case-based learning, dramatized role-play, and embodied modeling within a single

instructional design. Even fewer have formally developed, validated, and pilot-tested such an approach within

preservice teacher education in the Philippines. Recent literature continues to emphasize the need for multimodal

and research-informed strategies that correct misconceptions and support visualization of molecular phenomena

(Mhlongo and Govender, 2024; Abuhassna, 2024; Reyes and Constantino, 2024). This points to a clear gap in

the field. There is a lack of comprehensive, classroom-tested instructional models that combine contextualized,

dramatized, and embodied learning experiences to address persistent misconceptions about the Central Dogma.

The CODE Instructional Approach was developed to address this gap. CODE refers to Case-Organized,

Dramatized, and Embodied learning. It combines real-world biological case scenarios, dramatized simulations in

produce effective science instructional materials (Martin and Sun, 2022).

The local educational context strengthens the need for such an approach. Many preservice science teachers in

regional institutions begin their Biochemistry courses with limited prior knowledge of molecular biology and

often rely on memorization rather than conceptual reasoning. Recent findings indicate that multimodal and

interactive teaching strategies can substantially improve molecular biology understanding across different

learning environments (Mhlongo and Govender, 2024). These observations highlight the importance of designing

contextualized, embodied, and interactive instructional tools that match the learning needs of Filipino preservice

teachers.

To ensure curricular relevance, the CODE Instructional Approach was aligned with the learning outcomes of

Module 2, Lesson 2.5 of the PHSc108 Biochemistry course. These outcomes include explaining how DNA

Overall, this research presents a multimodal instructional framework for molecular biology education and

provides a replicable model for preservice science teacher training in the Philippines.

This study used a developmental research design guided by the ADDIE instructional model, which involves the

stages of Analysis, Design, Development, Implementation, and Evaluation. The model was applied to create and

validate the CODE Instructional Approach. To determine the effectiveness of the intervention, a one-group

Campus. This group represented the entire population of third-year BSED Science students enrolled in the course

for that semester.

Purposive sampling was used because PHSc108 covers Module 2, Lesson 2.5, which focuses on the Central

Dogma. Since the intervention specifically targeted this lesson, these students were the most relevant participants

for the development, validation, and pilot testing of the teaching guide. Participation was voluntary, and informed

consent was obtained from all students before data collection.

The CODE (Case-Organized, Dramatized, and Embodied) Approach was developed using the ADDIE Model as

follows:

role-play scripts, case narratives, embodied activity guides, and molecular modeling tasks. The pretest–posttest

assessment and validation rating sheets were developed in this phase. Adopted rubrics were used by the panel

of evaluators to examine content accuracy, clarity, pedagogical alignment, feasibility, and scientific

correctness.

included case analysis, dramatized simulations of transcription and translation, and embodied modeling of

molecular interactions. The teaching guide served as the primary reference for activity flow and sequencing.

the pretest–posttest and student reflections were analyzed to determine the validity, effectiveness, and

A researcher-developed 25-item test measured students’ understanding of DNA, RNA, transcription, translation,

and mutation. Seven evaluators reviewed the instrument using an adopted validation rating sheet that assessed

content relevance, clarity, scientific accuracy, cognitive demand, grammar, fairness, and feasibility.

2) CODE Teaching Guide Validation Rubric:

The teaching guide was evaluated using an adapted validation rubric based on established instructional design

tools. It examined ten criteria, including accuracy, alignment with learning outcomes, sequencing, engagement,

contextualization, differentiation, assessment integration, material feasibility, and visual presentation.

3) Student Reflection Instrument:

A semi-structured reflection form allowed students to describe their experiences with the CODE Approach. The

tool guided them to reflect on challenges, conceptual changes, engagement in activities, and the usefulness of the

Ethical approval was obtained from the Office of the Campus Chancellor. Participation was voluntary, and

All students indicated difficulty with at least one molecular process. Translation was the most challenging (6 of

struggled with codon–amino acid relationships, roles of mRNA and tRNA, and the intracellular mechanisms

Shapiro–Wilk

To determine whether the observed improvement was statistically significant, the Wilcoxon Signed-Rank Test

was performed. All twelve students obtained higher posttest scores, resulting in 12 positive ranks, 0 negative

ranks, and 0 ties.

The Wilcoxon test produced a Z-value of –3.068 with a p-value of .002, indicating a statistically significant