Early childhood education in Kenyan slums is characterized by limited resources and inadequate teacher training, leading to suboptimal educational outcomes for young children. A qualitative research design was employed, involving semi-structured interviews with 30 teachers from five randomly selected primary schools in Nairobi slums. Data collection also included observation of classrooms to capture practical application of training content. Teachers reported significant improvements in their pedagogical skills and classroom management after the training programmes, particularly in fostering positive learning environments and engaging students through interactive methods. The findings suggest that targeted teacher training can substantially enhance early childhood education quality by improving teachers' instructional practices and creating more stimulating learning spaces for children. School administrators should prioritise ongoing professional development opportunities for educators, while policymakers might consider integrating such programmes into national educational frameworks to ensure equitable access across different socio-economic settings.