When and how to use dual coding effectively in teaching
When and how to use visuals effectively: a meta-analysis of dual coding in the classroom by Briony Banks, Jennifer Curran, Rebecca Hall, Sam Sims and Stefanie Meliss.
About this research
Dual coding means using visuals, such as pictures or diagrams, alongside words in your teaching. Teachers need to know how to use dual coding effectively to support pupils’ learning.
Our study aimed to better understand why the impact of dual coding varies. This builds on the Education Endowment Foundation’s review of cognitive science in the classroom. Their review found that, while dual coding is generally beneficial to pupil outcomes, several factors may affect how well it works, and sometimes it may not work at all.
In this research, we conducted a meta-analysis of 56 studies of dual coding, systematically searching for and combining the results of all existing research. The studies were carried out in schools with pupils aged 4 to 18. We analysed how visuals were designed and used, the characteristics of pupils in the study, and the design of the research itself.
Findings
Our study found that:
- On average, dual coding had a positive and significant effect on pupils’ learning. But the effect of dual coding in a classroom setting can vary considerably. The way resources and lessons are designed is important for dual coding to have a positive impact.
- Secondary-age pupils benefited most from dual coding to support knowledge retention and understanding.
- Completing a task related to the visual, such as tracing pictures or filling in a diagram, did not make dual coding more effective.
- Not all visuals are equally effective. The biggest benefits occurred when interventions applied one of three principles from the Cognitive Theory of Multimedia Learning (Mayer, 2008, 2014): signalling (linking visuals to verbal explanations or written text); segmenting content meaningfully; and avoiding irrelevant details.
- To make more effective use of visuals, teachers could consider using them in: classes with secondary-age and further education pupils; in-person, whole-class teaching for all pupils; and teacher-paced or timed activities.
Read the research
Read a summary of our findings for educators.
Cite this paper
Banks, B., Curran, J., Hall, R., Sims, S., & Meliss, S. (2026). When and how to use visuals effectively: a meta-analysis of dual coding in the classroom. Ambition Institute.