This study aims to evaluate the effectiveness of an intervention program for preschool children in
an area where educational standards are poor. The participants, 129 children aged between 3 and
6 years, belonging to a public kindergarten in a Brazilian state with the second lowest human development
index were involved in this research. The children were divided into an experimental
intervention group and control group, where intelligence, memory, vocabulary, rapid automatized
naming, and phonological awareness were evaluated before and after an intervention. The results
show improvements in receptive vocabulary and rapid automatized naming in the experimental
group after intervention. The level of intelligence prior to intervention was able to predict 25% of
the vocabulary performance after intervention. Phonological awareness was predictive to nearly
26% of the performance in vocabulary after intervention only in the experimental group.