This study aimed to determine the effectiveness of Gagne’s model of instructional design on the attention and working memory capacity of students with attention deficit hyperactivity disorder. This study adopted a quasi-experimental design with pretest-posttest and a control group. The statistical population of the current research consisted of all fifth-grade female students with attention deficit hyperactivity disorder in Tabriz in the academic year 2021-2022. In this study, 30 students with attention problems (scores higher than 72 in the Connors Parent Questionnaire) were selected as the sample and randomly assigned to the experimental and control groups. The experimental group underwent eight training sessions, four sessions per week, each for 30 minutes, using the Gagne’s training model while the control group did not receive any training. It should be mentioned that the computer version of the selective and divided attention and working memory tests were used to collect data. The data were analyzed using multivariate analysis of covariance (MANCOVA) and SPSS 22 software. The results showed that Gagne’s model of instructional design is effective in increasing divided attention (P <0.048), selective attention (P <0.018), reducing reaction time (P <0.009), and increasing working memory capacity (P <0.047) in students with attention deficit hyperactivity disorder. Therefore, it is suggested that the content of courses requiring great attention and concentration be designed using Gagne’s model of instructional design and presented to students in order to increase the amount of divided attention , selective attention and working memory capacity and reduce reaction time.
