Using a randomized-control trial, this study evaluates a program designed to support Ghanaian kindergarten student-teachers during pre-service training through mentorship and in-classroom training. Several potential barriers to improved teaching quality and learning outcomes are examined. Findings show that the program improved knowledge and implementation of the national curriculum for individuals both when they were student-teachers and, the following year, when they became newly qualified teachers (NQTs). There were mixed impacts on professional well-being, increasing personal accomplishment and motivation but decreasing job satisfaction for NQTs. There were mixed impacts on teaching quality, with increases in child-led learning but decreases in some other aspects of quality. There were no impacts on NQTs’ student learning outcomes. The findings highlight system level challenges with both the posting of NQTs and the absence of support in their first teaching year. Implications for global early childhood education policy and teacher education are discussed.