Surveys in low- and middle-income (LMI countries) reveal persistently low levels of learning among children in disadvantaged communities. Against this background, our synthesis of ethnographies aims at a fresh interpretation of classroom practices to clarify instruction-related barriers to literacy attainments. The review focuses on the period from 1990, the year of the UN Declaration of Education for All, to 2014. Sixteen studies focusing on children up to Grade 4 from eleven LMI countries met criteria for methodological rigour. The synthesis, structured within socio-cultural and psycholinguistic frameworks, examined vignettes of teacher- and child-initiated talk and activities related to language and literacy learning. Trends captured include instructions that are light on explanation, skewed towards reinforcing orthographic knowledge, and leaving the advancing of children's broader linguistic and general knowledge to incidental learning. Learning from the peer group is common and, in bi- and multilingual settings, use of home language as a learning resource is uncommon. It is proposed that a cultural analysis of choral lessons, writing for learning, peer tutoring and community-specific preferences for language of instruction is required to understand whether embedding inference-focused interventions within these practices will promote more effective teaching and learning.