In this article, I explore language practices in Nigerian primary school classrooms against the backdrop of the policy of mother tongue education. Findings from the study show that there is a classroom bilingual practice that is rather unstructured in terms of curricular application and levels. The study shows that rather than implementing the country's mother tongue education policy, teachers have resorted to evolving a varied "policy" of bilingual instruction. The article also shows that the inherited colonial language--English--is used as early as the first year of the child's primary school education while the mother tongue continues to be used throughout the fourth year, when the transition to English medium should have commenced. Furthermore, the "untidiness" seems compounded by a regular use of code switching (CS) by teachers. The article concludes that there is a need for a pragmatic approach to language-in-education in Nigeria whereby room should be provided for the co-official use of English and mother tongue as well as a "supplementation" with CS where and when necessary. (Contains 5 tables and 7 endnotes.)