Objective: The present study aimed to examine the effectiveness of a multisensory educational intervention based on the Fernald method on the information processing speed of elementary school students with processing speed deficits.

Method: This applied research used a quasi-experimental design with a pretest–posttest control group. The population included all third- to sixth-grade students in public schools in Kerman during the 2024–2025 academic year. After screening with the Processing Speed Index of the Wechsler Intelligence Scale for Children–Fifth Edition (WISC-V), 30 students were selected through multistage cluster sampling. Participants were randomly assigned to an experimental group (n = 15) or a control group (n = 15). The experimental group received the Fernald multisensory intervention over one and a half months, consisting of 15 sessions of 45 minutes each, while the control group received no intervention. Data were analyzed using multivariate analysis of covariance in SPSS 26.

Results: After controlling for pretest scores, MANCOVA indicated a significant difference between groups in posttest information processing speed scores (F = 96.52, p < 0.01). The adjusted mean of the experimental group (M = 105.72) was higher than that of the control group (M = 84.67), and the effect size (η² = 0.598) indicated a strong intervention effect.

Conclusion: The Fernald multisensory intervention effectively enhances information processing speed in elementary students with deficits in this domain. By simultaneously engaging visual, auditory, tactile, and motor modalities and leveraging neural plasticity, it provides a practical, evidence-based strategy for improving core cognitive functions in educational and rehabilitation settings.