Background This study focuses on achievement emotions in a context of foreign language acquisition in a French‐speaking population. Aims Firstly, the reliability and construct validity of the Achievement Emotion Questionnaire were examined; the second aim was to compare the effectiveness of two teaching approaches, classical and task‐based learning and teaching ( TBLT ) on students' emotions over time. Sample This study involves 299 participants. Methods Achievement Emotions were rated with a self‐administrated questionnaire at the beginning of the academic year and at its end. Results To verify the psychometric aim, a series of confirmatory factor analyses were computed and showed that the original multifactorial structure proposed by Pekrun et al . (2010) had the best fit. For the second aim, the results showed that all of the achievement emotions reduced in intensity over the school year (apart from boredom) and this reduction is higher for the anxiety level of pupils in 6th grade with TBLT . Conclusions Implications for further research and educational practice are discussed.