A medium of instruction (plural: media of instruction, or mediums of instruction) is a language used in teaching. It may or may not be the official language of the country or territory. If the first language of students is different from the official language, it may be used as the medium of instruction for part or all of schooling. Bilingual education or multilingual education may involve the use of more than one language of instruction. UNESCO considers that "providing education in a child's mother tongue is indeed a critical issue". In post-secondary, university and special education settings, content may often be taught in a language that is not spoken in the students' homes. This is referred to as content based learning or content and language integrated learning (CLIL). In situations where the medium of instruction of academic disciplines is English when it is not the students' first language, the phenomenon is referred to as English-medium instruction (EMI).

In different countries and regions

Africa

Western Hemisphere

Brazil

Every public school uses Brazilian Portuguese as the medium of instruction, but no law prohibits the use of other languages in private schools. Many schools use other European languages (mainly because of the country's European heritage) such as English, German, Italian or French. Public schools also have mandatory English and Spanish but only once or twice a week.

Canada

United States

English is used, but in some schools, Spanish, French (in Louisiana), Hawaiian (in Hawaii), and local Native American/American Indian languages are used as well.

Asia

South East Asia

Australia and Oceania

Europe