This study examines the use of gamification as an innovative assessment approach to foreign language learning with 12-14-year-old students. A mixed methodology has been applied. Quantitative data have been collected from formative non-gamified and gamified assessments. Qualitative data was collected from a student questionnaire. The results were obtained from an international middle school where four groups of students, two in Grade 7 and two in Grade 8, engaged with gamified formative assessment. Findings show that gamification can provide a useful support mechanism in assessment success, and also on an emotional level as it lowers the affective filter, allowing the students to reduce potential anxiety and face the assessment with greater confidence. However, gamification had a small negative impact on otherwise high-performing students in the study, suggesting that gamification may not be appropriate in all contexts.