AGBO GABRIEL. Staff Development Programmes and Teachers’ Effectiveness in Public Secondary Schools in Kachia Local Government Area of Kaduna State, Nigeria. Journal of Education Research and Library Practice, Nigeria, v. 13, n. 8, 2026. DOI: 10.70382/ajerlp.v13i8.0115. Disponível em: https://africanscholarpub.com/ajerlp/article/view/1670.. Acesso em: 11 nov. 2026.