Summarize the contributions of Binet, Terman, and Wechsler to the evolution of intelligence testing

What will be an ideal response?

Alfred Binet devised a test to identify mentally subnormal children in France. The scale was a success because it was inexpensive, easy to administer, objective, and capable of predicting children's performance in school by expressing the child's score in terms of "mental age.". Lewis Terman and his colleagues at Stanford University revised and expanded Binet's work, leading to the development of the Stanford-Binet Intelligence Scale and the calculation of the Intelligence Quotient, or IQ, score. Terman also became a key force behind the adoption of IQ tests by American schools.

Terman's IQ was defined as the ratio of mental age divided by chronological age. David Wechsler set out to improve on the measurement of intelligence in adults. His changes resulted in two major innovations: the scales were less dependent on the subject's verbal abilities than the Stanford-Binet test, and he discarded IQ in favor of a new scoring scheme based on the normal distribution.