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The best predictor by far of how responsive a child is to instruction is the child’s intelligence. Intelligence tests, for all of their shortcomings, are reliable and valid ways of assessing intelligence, and they correspond quite well to academic achievement measures including grades and standardized tests. But despite being the best predictor, factors other than intelligence are also responsible for academic achievement. Aspects of a child’s personality, for example, are extremely important for doing well in school. The concept of “grit” has received a lot of attention recently, and it is just another word for determination, conscientiousness, and perseverance in the face of difficulty. Getting adequate sleep is necessary for optimal performance in school and the routes through which sleep facilitates performance are varied. Getting sufficient sleep allows better concentration and acquisition of new knowledge, better memory for what was learned, and better regulation of emotions.
A recent study from our lab illustrates the role of sleep in the link between intelligence and achievement. A sample of 282 4th and 5th graders with no diagnosed learning or sleep disorders was given intelligence and achievement tests and had their sleep monitored with wrist actigraphs for one week. Parents completed sleep diaries to cross-validate results from the actigraphs.
Intelligence was correlated significantly (r= .77) with achievement at the expected level. But the relations between intelligence and achievement were different for children at the higher versus the lower end of the distribution of intelligence. For children with higher intelligence, intelligence was strongly related to achievement when children’s sleep was good, but the correlation between intelligence and achievement was lower when children did not sleep well. Children who score highly on intelligence tests and not as well on tests of academic achievement are often called underachievers. Underachievement can be the results of numerous factors, and sleep of insufficient duration and quality is likely an important determinant for many children.
During the summer school break is a good time to estimate what a child’s sleep needs are. Without early awakenings that are required for school, parents can measure a child’s typical length of sleep and use that as a goal for the school year. Our research has found that regularity of sleep schedule is important for optimal academic and emotional functioning. Summer affords more flexibility in when children go to bed and wake up, and maintaining a relatively stable sleep schedule during summer will ease the transition to the beginning of the school year.
Erath, S. A., Tu, K. M., Buckhalt, J. A., & El‐Sheikh, M. (2015). Associations between children's intelligence and academic achievement: The role of sleep. Journal of Sleep Research, 24, 510-513.
