We evaluated the long-term effects of a supplemental, small-group kindergarten vocabulary intervention in fall and spring of first grade and winter of second grade. Participants included students from two studies, an initial efficacy study and a subsequent replication study, identified as at risk for language and learning difficulties, who were…

We investigated whether individual differences in overall receptive vocabulary knowledge measured at the beginning of the year moderated the effects of a kindergarten vocabulary intervention that supplemented classroom vocabulary instruction. We also examined whether moderation would offset the benefits of providing Tier-2 vocabulary intervention…