Recall accuracy for six transformational types and six degrees of grammatical-ness of three-word sentences was measured after 0, 3, 6, 9, 12 and 18 seconds. The results obtained on a sample of 216 children of three age groups were compared with the findings of Peterson and Peterson (1959). From the mean scores and ANOVA results it may be concluded that retention of sentential material is a joint function of the recall interval, event certainty and age.