The effects of spaced versus massed distribution instruction on EFL learners' vocabulary recall and retention

The current study investigates the effect of massed and spaced instruction on vocabulary recall and retention. To fulfill this objective, 75 Iranian pre-intermediate EFL learners (16 to 19 years) took part in 15 sessions of 60 minutes. The participants were randomly divided into three experimental groups; a spaced distribution group (n = 25), a massed distribution group (n = 25) and a control group (n = 25). The massed distribution group had one intensive session on learning the target vocabulary; the spaced distribution group had three sessions at irregular time intervals, and the control group received no vocabulary-focused instruction. Using a before and after design, students were retested after 5 weeks. To collect data, a receptive vocabulary test was administered as both the pretest and the posttests. The results of One-way ANOVA indicated that the spaced distribution group significantly outperformed the massed distribution group on both immediate and delayed posttests. The results propose that EFL practitioners should synthesize spacing as a beneficial teaching technique into the curricula, instruction and educational materials to promote vocabulary learning in real classroom setting.