Involvement in their children's education through the Competency-Based Curriculum (CBC) significantly impacts the mental health outcomes of parents, necessitating a deeper understanding of how these educational demands influence parental well-being. This study examines the mental health outcomes of parents with children enrolled in the CBC in primary schools in Nairobi County, Kenya. Utilizing Cognitive Behavioral Theory (CBT), the research employed a quantitative approach with a cross-sectional survey design targeting parents with children enrolled in the CBC in primary schools. A multi-stage sampling technique resulted in a sample size of 376 parents. Data were collected using structured questionnaires, including the Parenting Sense of Competence (PSOC) scale, Multidimensional Fatigue Inventory (MFI), Parental Stress Scale, and New General Self-Efficacy Scale. Statistical analysis using SPSS Version 25 involved descriptive methods. The findings revealed generally positive mental health outcomes, with high levels of parenting satisfaction and self-efficacy, alongside moderate levels of mental fatigue and stress. These results align with CBT, emphasizing the role of positive beliefs and effective coping strategies in maintaining mental health. The study concludes that while CBC aims to enhance learning, it also creates challenges for parents that impact their mental health.