While full immersion in a language is the best and fastest way for a student to learn a new language, there are various extraneous factors to be taken into account. What affect will immersion in the culture have on the culture itself? How much actual learning takes place in enclaves? Should there be established ESL programs in place as entry requirements for inclusion in mainstream schools? These are some of the more pressing issues or problems identified with teaching ESL.
When speaking of the effects of immersion on the culture itself, the culture is that of the native-language speakers in the school settings. What effects do ESL students have on the learning of native speakers, who are trying to learn a subject other than the language? The ESL student in turn is struggling to learn English to communicate while at the same time learning the subject that is being taught. This disadvantages the ESL student because his or her learning abilities are split between the language and the subject. It also disadvantages the native students, who will have their teacher's time monopolized by the ESL students.
A problem with any culture in the world is that people will always seek out their own kind. In any major city of the world there are enclaves where people of similar ethnic backgrounds set up home and businesses.There have been numerous cases of immigrants living in Australia or the United States for more than twenty years who still do not speak any English. In these insular societies there is no pressure to learn ESL when there is no need to. Admittedly, many immigrants come to the West seeking work or a better life, and the need to earn a living will preclude any formal study. Therefore they pick up English on the job. Children of immigrants, however, often speak their parents' tongue fluently and sometimes allow themselves to pick up their parents' accents as well. This is not a problem, but acquiring their parents' linguistic errors in English is.
There are some solutions to this situation that are being implemented around the globe. Many countries have ESL and EFL (English as a foreign language) schools and private colleges. A solution to the problems of ESL encroaching on mainstream teaching time in high schools is to require teenage students to attend ESL courses that will bring them to a age-appropriate level of language development before they are allowed to enroll in mainstream schools. This way they will study nothing but the English language for six hours a day in an environment where their native tongues are not allowed. A teenager will require roughly three months of this intensive learning to reach the advanced level and graduate. Preteen children would not need to attend such a course as they can still acquire a new language naturally by immersion. Although education policies in most countries advocate full inclusion for all students, nations can still adopt language policies that do not infringe on students' human rights. For instance, Australia accepts thousands of foreign students into its high schools, colleges, and universities each year, but before they can enroll, they must complete ESL courses to the specifications of each institution. The upshot of this policy is that no student is impeded in his or her learning by language deficiency.