How stable are IQ scores, and how well do they predict academic achievement, occupational attainment, and psychological adjustment?

What will be an ideal response?

Preschool scores predict less well than later scores because, with age, test items focus less on concrete knowledge and more on complex reasoning and problem solving, which require different skills. Another explanation is that during periods of rapid development, children frequently change places in a distribution. One child may spurt ahead and reach a plateau; a second child, progressing slowly and steadily, may eventually overtake the first. Finally, IQ may become more stable after schooling is under way because daily classroom activities and test items become increasingly similar. Then, variations among children in quality of school experiences and in mastery of those experiences may help sustain individual differences in IQ.
Students with higher IQs also get better grades and stay in school longer. Beginning at age 7, IQ is moderately correlated with adult educational attainment. Some researchers support the view that an intelligence test is, in fact, partly an achievement test, and a child's past experiences affect performance on both measures. Others favor the idea that heredity contributes strongly to individual differences in IQ.
Research indicates that childhood IQ predicts adult occupational attainment just about as well as it correlates with academic achievement. By second grade, children with the highest IQs are more likely, as adults, to enter prestigious professions, such as engineering, law, medicine, and science. Educational attainment is actually a stronger predictor than IQ of occupational success and income.
IQ is moderately correlated with emotional and social adjustment. Higher-IQ children and adolescents tend to be better-liked by their agemates. Besides IQ, good peer relations are linked to patient but firm child-rearing practices and an even-tempered, sociable personality, both of which are positively correlated with IQ.
In sum, IQ predicts diverse life success indicators, but does so imperfectly. These findings provide strong justification for not relying on IQ alone when forecasting a child's future or making important educational placement decisions.