If someone could choose a reward of $50 today or $55 in three months, it is likely the person receiving the money would choose $50 today because it is an immediate reward, even though in the long term the second option would be more beneficial.

Same rule applies to school. Each day when deciding whether to log onto Twitter or finish homework, the immediate reward to the brain would be Twitter. However, the long term reward of receiving good grades would be more beneficial.

The advice here is that the brain is not accustomed to weighing long term benefits at the same level as immediate rewards. In order to thrive in school, create immediate rewards. Gain something such as computer time or dessert only after daily obligations are complete.  This will not only help with procrastination and school, but with work ethic needed to apply the same ideas to other aspects of life such as losing weight or working out.