This inquiry explores the impact degree of one individual factor, gender, on the level of English skill achieved in two distinct groups of intermediate-level Catalan Spanish teen learners of English as a foreign language: the 1 year younger first group (Group A) follows formal instruction (FI) and in parallel content and language integrated learning (CLIL) instruction (FI + CLIL), thus receiving some ‘extra’ CLIL hours. The second group (Group B) follows a FI only program. Data were obtained both for receptive and production skills, save speaking, and were statistically studied via a one academic year pretest–posttest design. At variance with suppositions, findings affirm that female participants surpass male participants in both acquisition contexts albeit not in all examined abilities and fields.