It seems there are huge differences in vocabulary knowledge between young children in
this country. These differences develop early in life and seem to remain constant throughout the
elementary school period. There has been little attention to this component of reading in the
early childhood years despite it being such a critical time for vocabulary development. Recent
research is showing promising results in developing and evaluating new methods for vocabulary
instruction. Educators need strategies that are both appropriate for preschool children and
effective in promoting vocabulary learning in children who are not yet reading independently.
The goal of this study is to evaluate the effectiveness of a structured, comprehensive
framework for preschool vocabulary instruction consisting of a combination of researchsupported
strategies implemented during storybook read-aloud sessions for two lengths of time.
The study used a quasi-experimental, split-plot design with two between-groups factors,
condition (instructional intervention vs. comparison) and implementation time (short term vs.
long term) and one within-groups factor, time of measurement (pretest vs. posttest). Participants
were teachers and 4- and 5-year-old children drawn from area preschools and child-care centers.
Quantitative data analysis revealed that the instructional intervention was an effective
method for teaching targeted vocabulary words to preschool students. Both the short-term and
long-term instruction periods were effective, the long-term condition much more so and obtaining a large effect size. Further analysis showed that the intervention did not have
differential effects on students’ learning according to prior levels of vocabulary knowledge;
students with low vocabulary levels were able to learn the targeted words.
Evidence of positive learning outcomes supports the instructional intervention and offers
teachers a structure for storybook read-aloud sessions that addresses goals of an emergent
literacy curriculum effectively. The lack of differential effects suggests that the approach may
be a key to increasing the rate of vocabulary learning that is crucial for at-risk students. It would
take more instructional time to teach targeted words for four days instead of two, but knowing
more words leads to increased incidental learning of words making the extra instructional time
beneficial to long-term word learning and achievement.