“…A total of 28 studies met the inclusion criteria and were included in the meta‐analyses. Of the 28 studies, 24 studies focused on samples of 18 years and older (e.g., college students, graduate students, young adults), including Chinese learners of Japanese (Xu, , ; Xu & Matsumi, ), and four studies used samples from the elementary school level (Muis et al, ) and the secondary school level (Ehly et al, ; Fukaya, ; Hoogerheide, Loyens, & van Gog, , Experiment 1). These studies included 28 group comparisons (1,283 participants who completed an immediate or delayed test) for a preparing‐to‐teach group versus a control group (see Table ) and 16 group comparisons (751 participants who completed an immediate or delayed test) for teaching with preparing‐to‐teach group versus a control group (see Table ).…”