This study focuses on the degree of influence of one individual factor, namely gender, on the level of English competence attained in two different groups of intermediate-level Catalan Spanish adolescent learners of English as a foreign language: the first group (Group A) is 1 year younger and follows formal instruction (FI) and in parallel content and language integrated learning (CLIL) instruction (FI + CLIL). That is, the group receives some 'extra' hours which are CLIL hours. The second group (Group B) follows a FI only programme. Data were elicited both for receptive and production skills, except speaking, and were statistically analysed using a pretest-posttest design over one academic year. Results obtained, contrary to expectations, confirm that female participants are better than male participants in both contexts of acquisition although not in all skills and domains analysed.