MTB-MLE is an education system that uses a student's mother tongue as the primary language of instruction. It begins teaching basic reading, writing, and academic concepts in the student's most fluent language before gradually introducing additional languages. Theories of language acquisition suggest students learn best when initial instruction is in their native language as it allows them to build on prior knowledge and develop cognitive skills through meaningful participation and discussion in a familiar language. MTB-MLE aims to provide strong literacy and numeracy foundations, cognitive development, and a bridge to additional language learning.