The impacts of spaced and massed distribution instruction on EFL learners’ vocabulary learning

Abstract

This study intended to investigate the effect of spaced and massed distribution instruction on vocabulary learning. To fulfil this objective, 68 Iranian pre-intermediate EFL learners (14–16 years) participated in 16 sessions. The participants were randomly divided in to two experimental groups; spaced distribution group (n = 34) and massed distribution group (n = 34). The massed distribution group had one intensive session on learning the target vocabulary; the spaced distribution group had three sessions at irregular time intervals. Using a before and after design, students were retested after 8 weeks. To collect data, a vocabulary test was performed as the pretest and posttest. The results of the paired samples t test and One-way ANCOVA indicated that the spaced distribution group significantly outperformed the massed distribution group on the posttest (effect size.75). The results propose that EFL practitioners can synthesize spacing as a beneficial teaching technique into the curricula and educational materials to promote vocabulary learning.