Short answers, pulled from the story.
Self-esteem is confidence in one's own worth, abilities, or morals. Smith and Mackie define it as the positive or negative evaluation of the self, distinct from the self-concept, which is what we think about the self. It encompasses beliefs such as "I am worthy" along with emotions like triumph, despair, pride, and shame.
The concept of self-esteem originated in the 18th century in the writings of the Scottish enlightenment thinker David Hume. Self-esteem was later identified as a distinct psychological construct by the philosopher and psychologist William James, who divided the self into the "I-self" and the "Me-self."
Self-esteem is typically assessed using self-report inventories. The most widely used is the Rosenberg self-esteem scale, a 10-item scale developed by Morris Rosenberg in the mid-1960s. The Coopersmith Inventory uses a 50-question battery, and implicit measures introduced in the 1980s include the name letter task and the Implicit Association Task.
No, inflating students' self-esteem by itself has no positive effect on grades, and Roy Baumeister has shown it can actually decrease them. Research indicates high self-esteem is generally a result of high academic performance rather than its cause.
The Task Force on Self-Esteem and Personal and Social Responsibility was set up and funded in California in 1986 through the work of assemblyman John Vasconcellos. Its scholars found only very small associations between low self-esteem and its assumed consequences, and the task force disbanded in 1995.
Self-esteem typically declines from ages 4 to 8 as children compare their real and ideal selves, then rises rapidly during adolescence and young adulthood. It increases gradually through middle adulthood, peaks around ages 60 to 70, and then declines again in later life.
Self-esteem and narcissism are not interchangeable, sharing only positive self-regard as a main feature. Narcissistic self-appraisals are exaggerated and defined by entitlement, exploitativeness, and dominance, whereas non-narcissistic positive self-views are relatively modest. The overall correlation between the two is only moderate.