Wouldn't the fourth grade be easier if we could go through it now, as adults? Is it because our knowledge of state capitals is so encyclopedic that we wouldn't have to crack a book? No. The real change is the development of our brains over time, particularly a system known as the frontal executive network. This part of the brain is responsible for much of what we value in successful students: bringing us the ability to set goals, organize, memorize complex information, and resist distracters.
We now know this is the last brain region to develop, with a growth spurt in the teenage years, and full maturity around age 21 or 22. Ironically, the system of the brain which allows us to be great at studying isn't fully on line until college is over! This is the central problem that The neuroscience of earning A's will address. Much of the frustration during homework time for parents stems from this basic problem. Children forget assignments, don't prioritize their time, and have trouble resisting distracters during homework. Neuroscience research gives us a framework for understanding why this happens with normally developing children.
The good news is that a new generation of brain imaging technologies has changed what we know about how we learn: demonstrating ways in which we can boost the executive function of our children, what to avoid that dampens executive function, and intriguingly, how we as parents can literally "lend children our frontal networks," using specific techniques to structure homework so that children can learn as effectively as if their frontal networks were more mature.