One-Way Immersion

It was designed to create the same kind of communicatively-rich conditions that characterize first language acquisition, particularly creating desire in the students to learn the L2 in order to engage in meaningful communication.

Origin: One way immersion programs were first developed in Canada in the 1960s. It is the most common form of immersion program in that country

• Teachers seek to develop students functional competence in the L2 in addition to normal levels of L1 competence, grade-level academic achievement, and appreciation for the target language group´s language and culture. 
• Language learning is content based, which means that French is learned through maths, science, and social studies.
• The teacher is usually the only native speaker model with whom the students interact.

• It is common in kindergarten and the early part of first grade to hear students using English while the teacher uses French. However as children progress through the grades, they are encouraged to use more French with teachers and peers. Initially literacy instruction is in French, and English literacy skills are typically introduced in second grade.

• By sixth grade about half the curriculum is in English and half in French.
• In 1971 One Way Immersion was introduced on United States. It was established the first early total Spanish immersion program
• It was similar to Canadian models in that all curriculum in kindergarten and first grade was delivered in Spanish and teachers presented themselves as monolingual in Spanish until English was introduced for the first time in second grade.

The goals of immersion programs for majority language children in the United  States were:

• To produce linguistic and cultural enrichment context within the school system.
• To create schools with a balanced ratio of ethnolinguistic groups of the area, and for English L1 children living in communities with non-English-speaking populations to become bilingual.

Criticism: It is very difficult to develop this program in public schools, where English is not taught from earlier grades and teachers of the rest of the subjects are not bilingual, except in some private bilingual schools. For instance, The Mackay School in Viña del Mar is bilingual, hence, according to the mission of the school, this methodology tries to integrate British values through the use of English in all the subjects.

Source:
Potowski, Kim (2007). "Language and Identity in a Dual Immersion School". Multilingual Matters Limited.7-9
Hollingsworth, Lindsay Kay. «Developing English and Spanish Literacy in One-Way Spanish Immersion Program.» 2013. 53.