Writing for Others, Learning for Yourself: Teaching Expectancy, Explaining to an Absent Audience, Creating Teaching Materials, and Watching Dialogues
Only expecting to teach averages g = 0.41 in samples aged 18 and over; no effect was detected in under-18 samples or among Japanese students. Expecting to teach and then writing an explanation or recording a video for an absent audience averages g = 0.48; teaching face to face is 0.84, from very few comparisons. A meta-analysis of creating teaching materials for others averages 0.17, with few studies of written materials. All of this comes from short lab materials; no study has tested writing a public article for strangers.