Intelligence
Genesee, F. 1976. `The role of intelligence in second language learning.' Language Learning 26: 267-80.

Aptitude
Wesche, M.B. 1981. `Language aptitude measures in streaming, matching students with methods, and diagnosis of learning problems' in K. Diller (ed.): Individual Differences and Universals in Language Learning Aptitude. Rowley, Mass.: Newbury House. pp.119-39.

The case of CJ
Obler, L.1989. `Exceptional second language learners' in S. Gass, C. Madden, D. Preston, and L. Selinker (eds.): Variation in Second Language Acquisition, Vol. IL. Psycholinguistic Issues. Clevedon, UK/Philadelphia, Pa.: Multilingual Matters. pp.141-59.

Motivation and attitudes
Gardner, R.1985. Social Psychology and Second Language Learning.. The Role of Attitudes and Motivation. London: Edward Arnold.

Inhibition and second language learning
Guiora, A., B. Beit-Hallahmi, R. Brannon, C. Dull, and T. Scovel.1972. `
The effects of experimentally induced changes in ego states on pronunciation ability in a second language: An exploratory study.' Comprehensive Psychiatry 13:139-50.

Learning styles and learner strategies
Reid, J. 1987. `The learning style preferences of ESL students.' TESOL Quarterly 21 / 1: 87-111.
Oxford, R.1990. Language Learning Strategies: What Every Teacher Should Know. New York: Newbury House.

Age of acquisition
Johnson, J., and E. Newport. 1989. `Critical period effects in second language learning: The influence of maturational state on the acquisition of English as a Second Language.' Cognitive Psychology 21: 60-99.

Brown,H.D.: Learner Variables I: Teaching Across Age Levels
On occasion people who are quite unaware of the language teaching field will walk into my office at the university and ask me something like, "Since English is my native language, I won't have any problem teaching it will I?" Or they might ask, on the eve of their departure to Indonesia (without the slightest clue of who their future students will be), "Can you recommend a good textbook for my students?" Other naive inquirers who have just a little exposure to the vastness and complexity of the field still might assert, "I would like to learn how to teach ESL. Can you recommend a good workshop?" Such hopes are fueled by occasional advertisements in local newspapers that promise you lifelong employment as an English teacher (in exotic places across the seas) if only you'll attend someone's weekend seminar (or two) and, of course, cough up a fairly hefty enrollment fee.

You have already begun to get a taste of the array of questions and issues and approaches and techniques that must be included in your training as a language teacher-a complexity that can hardly be effectively covered in a weekend workshop. Part of this complexity is brought on by the multiplicity of contexts in which languages, and English more so than any other language, are learned and taught. Even if you could somehow pack up a suitcase full of the most current teaching resources, you would still have to face the question of who your learners are, where they are learning, and why they, are learning.
This chapter begins to deal with contextual considerations in language teaching. In this chapter, context is addressed in terms of the learner variable of age. Chapter 7 deals with the learner variable of language proficiency (beginning, intermediate, and advanced). And Chapter 8 grapples with several complex variables introduced by sociopolitical contexts of teaching (country, societal expectations, cultural factors, political constraints, the status of English), by the institution one is teaching in (school, university, language school, adult education, vocational/workplace courses), and by the implied purposes for learning English (academic, technical, social, cultural immersion, enrichment, survival). Each of these considerations is essential to incorporate into your choices of techniques, lesson organization, and supporting materials.