This one that appeared in Science last year, for example, demonstrates that even simple retrieval practice, where students are just supposed to repeat what they already learned gives considerably improved results on various achievement tests down the line than many other educational interventions.
たとえばこれは 去年の サイエンス誌に 載った研究ですが 習ったことを 単に繰り返すだけの 単純な復習問題が 他の学習方法よりも 試験結果を大きく向上させる ということが分かりました