This study explores prototypical word associations in EFL learners' mental lexicon to determine how they categorize the words retrieved in response to prompts in a lexical availability task. We compare two groups of Spanish EFL learners: sixty children in the sixth grade of primary education and sixty adolescents in the ten grade of secondary school education(fourth year of ESO) The study aims to (1) determine whether adolescents retrieve a higher number of words than children, (2) ascertain whether there are similarities or differences in the prototypical word associations and levels of categorization observed in response to two semantic categories by two groups that differ in age and language level, (3) ascertain whether there is evidence of the universality of prototypes in semantic categories that differ in compact and dispersed natures (i.e., shared and non-shared responses). The results from this study suggest that: (1) there are differences in the words retrieved by the two groups, (2) there are convergences in the most available and prototypical word associations despite differences in age and language level; and (3) there is evidence of the universality of prototypes in each semantic category, given that the responses of both groups of informants are similar. [For the complete volume, "Lexicon Exploration in English and Spanish Learners. Educational Linguistics. Volume 67," see ED676344.]