<p>The research points to the existence of a strong correlation between the previous knowledge of children regarding language and phonological awareness, and success in reading and writing acquisition. This study presents the evaluation of an intervention program, with 869 children in the last year of pre-school education (52.5% boys) between 4 years and 10 months and 6 years and one month. Of these 373 were part of the intervention group. The results’ evaluation resorted to measures of language and phonological awareness. The results indicated the intervention group presents statistically higher values in all dimensions in the post-test. The magnitude of the effect was greater in the intervention group. The results support the effectiveness of this program in promoting language development and phonological awareness.</p>