Is it better to study in the morning or at night? Science says there is no one answer. Some people are morning types, and others are night types. Teenagers often become more of a night type until about age 20.

In some studies, children did better on tests at their own best time of day. So find your best time for hard work. Also, try to memorize things before you sleep.

People have long argued about whether morning or night is the best time to study, but science gives no single answer. It depends on your chronotype, your body clock's natural tendency to be active earlier or later in the day. In 2004, Roenneberg and his team surveyed about 25,000 people and found that people become more night-oriented through childhood and the teenage years, reaching a peak around age 20.

In 2007, a study of children aged 11 to 14 found that they tended to score higher on parts of an intelligence test when it was given at their own best time of day. So do difficult work when you feel sharp, memorize before sleep, and practice at the time of your real exam.

The debate over whether studying is more effective in the morning or at night has no universal winner, because people differ in chronotype, the natural timing of their daily rhythms. In 2004, Roenneberg and colleagues surveyed about 25,000 people and found that individuals shift toward a later, more night-oriented pattern through childhood and adolescence, peaking at around age 20 before gradually moving back.

They even proposed this peak as a marker for the end of adolescence. This suggests that teenagers' late nights are partly biological rather than simply a matter of laziness. Related research points to a synchrony effect: performance may be better when tasks are done at one's optimal time of day. A 2007 study of 11- to 14-year-olds, for instance, found higher fluid intelligence scores when testing matched the child's chronotype.

The evidence, though, has limits. The large survey relied on questionnaires, the synchrony studies were small to medium in size, and the effect appears mainly in certain types of tasks and has not always been replicated. Practical advice is therefore modest: schedule demanding work for your sharpest hours, memorize before sleep, avoid cutting sleep, and rehearse at the time of day your exam will take place.