Psychological Flexibility and Emotional Trajectories During a Semi-High-Stakes Mathematics Exam: Integrating Acceptance and Commitment Therapy With Control–Value Theory

Background. Exams are a common source of intense emotions in adolescence, requiring effective regulation for performance and well-being. Psychological flexibility (PF), the ability to stay open to difficult thoughts and feelings while pursuing meaningful goals, and psychological inflexibility (PI), involving avoidance and self-criticism, represent adaptive and maladaptive regulation styles that remain understudied in adolescents. Aims. We examined whether PF/PI is associated with adolescents’ emotional trajectories during a semi-high-stakes mathematics examination and whether these associations differ by gender or mathematics performance. Sample. Participants were 694 Finnish Year 8–9 students (48.7% girls). Methods. Before the examination, students completed the Children’s Psychological Flexibility Questionnaire (CPFQ) and subsequently reported their happiness, relaxation, frustration, and boredom across seven phases of the examination. Linear mixed-effects models estimated emotional trajectories and their associations with PF factors (Committed Action and Awareness; Acceptance and Defusion; Fusion and Self-Judgement), gender, and mathematical performance. Results. Happiness and relaxation declined during the examination and recovered afterward, whereas frustration and boredom increased. Committed Action and Awareness was associated with greater happiness and phase-specific variations in frustration, while Acceptance and Defusion with higher relaxation and a stronger late-exam rebound. Greater PI (lower Fusion and Self-Judgement) was linked with lower positive and higher negative emotions. Higher mathematical performance was associated with greater happiness and relaxation and lower boredom, and a gender interaction showed greater boredom among boys high in PI. Conclusions. Strengthening PF skills, particularly acceptance, defusion, and value-driven action, may help adolescents manage examination stress, sustain engagement, and reduce boredom in academic settings.