In a 2015 study, for example, researchers at York University in Toronto found students spacing out a lecture and a review quiz boosted test performance. The students attended a 45-minute lecture on meteorology. Half the students took an online quiz one day after the lecture, while the other half took the quiz eight days later. All of the students took a final test five weeks after their respective quizzes. Students who took the quiz eight days after the lecture performed significantly better on the final test than the other students, suggesting that spaced learning can enhance long-term memorization.
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