Stephen Krashen: Theories, Biography & Quotes

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  • 0:04 Who Is Stephen Krashen?
  • 1:23 Acquisition-Learning…
  • 2:05 The Monitor & the…
  • 3:10 The Natural Order Hypothesis
  • 3:52 Affective Filter Hypothesis
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Lesson Transcript
Instructor: Michael Gott

Mike is a veteran of the New Hampshire public school system and has worked in grades 1-12. His role has varied from primary instructor to special needs support.

Stephen Krashen is a linguistics professor at the University of Southern California. He is known for his theory of second language acquisition. This theory draws upon psychology, linguistics and educational theory.

Who Is Stephen Krashen?

Stephen Krashen is an Emeritus Professor of Education at the University of Southern California known for his theory of second language acquisition. He's also the cofounder of the Natural Approach, as well as the creator of sheltered subject matter teaching. He's the author of books on the subject of second language acquisition. Second language acquisition is the process of learning a second language different from your native language. Stephen Krashen's theory is used primarily in the United States across ESL (English as a second language) classrooms. Despite its influence across the country, it's regularly criticized for its lack of scientific research and de-emphasis on grammar.

Krashen's theory is comprised of five distinct theories. In order to properly understand this theory, we must first establish the difference between acquisition learning as a way to develop language skills. Acquisition is an organic method in which the learner develops language skills from immersion in it. Simple examples of acquisition would be a child learning his or her native tongue by simple immersion or a person who moves to a foreign country and picks up the language without classes but from need and daily interaction. Learning, by contrast, is a deliberate process of developing language skills through structured activities with a conscious focus and emphasis on grammar and proper form.

Acquisition-Learning Hypothesis

The first element of Stephen Krashen's theory hypothesizes that language is best acquired through a combination of acquisition and learning, with a much stronger emphasis on acquisition.''Acquisition requires meaningful interaction in the target language - natural communication - in which speakers are concerned not with the form of their utterances but with the messages they are conveying and understanding.''

Krashen emphasizes the importance of authentic communication based on seeing language as a tool for the exchange of ideas. Krashen believes learning proper grammar before one can communicate on a real level is a waste of time. This acquisition and learning theory is the first part of Krashen's five point second language theory.

The Monitor & the Input Hypothesis

The second part of Krashen's theory is the monitor hypothesis, which works to explain the correlation between acquisition and learning. When a person monitors their speech for grammar, this is the practical result of learning. Through learning, we monitor what has been learned through acquisition. Excessive learning after acquisition can lead to overly edited speech that hurts communication because it's too refined for general communication.

The input hypothesis is Krashen's attempt to explain how a person can acquire a second language. This hypothesis has no connection to learning, only acquisition. In the input hypothesis, Krashen states that acquisition occurs best when the learner is exposed to second language input at a slightly higher level than they are competent at. This is based upon natural verbal communication, where acquisition doesn't occur in a formal class structure. Krashen recommends language teachers design their courses above the current level their students are at. As Krashen states, ''Language acquisition does not require extensive use of conscious grammatical rules, and does not require tedious drill.''

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