The objective of this study was to examine the effect of Mindkeys Training, a mindfulness-based educational intervention, on attention, self-control, and aggressiveness in third-year primary school pupils. In order to achieve this aim, a switching replications design was used. Two groups of third year primary students (nGE1 = 40; nGE2 = 33), aged between 7 and 10 years old (M = 8.08; DT = 0.49), had the intervention at different time points, such that while one served as the experimental group, the other served as the control group. Longitudinal differences were examined in both groups, and cross-sectional differences were examined between the two groups at three time points; at the start of the study, and following the intervention with each group. To that end, measurements of problems of attention, deficits of self-control, and aggressiveness for students were obtained via a teacher rating scale. The intervention program demonstrated a positive effect on the reduction of pupils' attention problems, deficits of self-control, and aggressiveness. The effects were greater on the cognitive variables that the intervention worked on directly (attention and self-control). Attention was the variable on which the intervention exhibited the longest term effects.
Keywords: aggressiveness; attention; intervention; mindfulness; school; self-control.