Introduction

Numerous studies – age-related or not – have shown that measures of input, such as cumulative hours of instruction, hours spent in stays abroad or frequency of (extracurricular) contact with the target language (TL), are significantly associated with learners' foreign language (FL) proficiency and oral performance, respectively. As pointed out earlier, the classroom is a minimal-input environment, and the learner in this context is by definition a 'part-time learner' (Kennedy, 1973: 75, quoted from Singleton & Ryan, 2004: 201). According to some authors (e.g. Skela & Dagarin Fojkar, 2009), the first 5 years that a child spends acquiring his/her native language in a naturalistic setting is equal to studying an FL in a school context for 90 years. Or to turn the argument around, the amount of input that a child receives in 3 weeks while acquiring his or her native language is equivalent to the sum total of learning an FL in a school environment for 1 year or 200 school hours (see Singleton & Ryan, 2004). Rifkin (2005, quoted in Muñoz, 2012b: 2) thus suggests that students 'must immerse themselves to reach advanced proficiency, either in a domestic immersion program or abroad'.

In this chapter, we look at different types of provision of FL teaching, including domestic immersion programmes and their effects on the linguistic competence of learners with a different age of onset (AO), as well as their interaction with extracurricular exposure and the influence of the latter. It is our main goal to offer a critical empirical examination of content and language integrated learning, generally known as CLIL, in state educational institutions in order to better identify its strengths and weaknesses compared to regular English as a foreign language (EFL) instruction. As mentioned in Chapter 1, the notion of CLIL will be used as a cover term for both CLIL and immersion, following Mehisto et al. (2008). Specifically, in the Swiss context, it refers to late CLIL in secondary school.