Educational psychology provides a scientific basis for understanding and improving student motivation and achievement. This comprehensive review integrates recent evidence on how cognitive, emotional, and contextual factors influence motivation and performance in secondary schools. Key findings show that strong motivational beliefs (e.g. self-efficacy, intrinsic value) significantly predict learning outcomes beyond measured intelligence. Interventions that teach metacognitive and self-regulated learning (SRL) strategies yield large academic gains. Likewise, emotional factors – including emotional intelligence and supportive teacher–student relationships – indirectly support achievement by enhancing engagement. Socioeconomic and cultural contexts also play a major role: students from disadvantaged backgrounds tend to have lower achievement unless motivational mediators (such as positive attitudes and expectations) are fostered. Finally, well-designed educational technologies (e.g. interactive apps, gamification) can boost motivation and self-confidence when aligned with learning goals. This paper’s methodical literature review identifies evidence-backed psychological principles and models (e.g. self-determination theory, social-cognitive theory, expectancy-value theory) to explain these findings. It concludes with practical recommendations: educators should integrate metacognitive training, socioemotional learning, and engaging technology into curricula, while policymakers address resource inequities and teacher development. By leveraging educational psychology, secondary schools can more effectively nurture motivated learners and improve academic outcomes.