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Mental help.net: Motivating Adolescents Toward Responsible Choices Part I
Explains the difference between extrinsic and intrinsic motivation in the context of parenting a teenager. Then discusses the difference between controlling a teen versus giving them choices. (Published: Feb. 3, 2015)
Khan Academy
Khan Academy: Test Prep: Mcat: Behavior: Motivation and Attitudes: Motivation Article
Explains the basic theories of motivation.