This study aimed to understand how children reflect about learning, report their regulation of learning activity, and develop their performance in contemporary English as a Foreign Language instructional settings. A quasi-experimental design was used with one experimental group working in a self-regulated learning computer-supported instructional setting and two control groups (the first with self-regulated learning and no computer support, the latter with no training) with process diary data and pre- and posttests (diary task entries, n = 440). A multilevel linear analysis of the diary data showed diverse growth rates of self-regulated learning activity throughout time between the three groups. Item Response Theory demonstrated that a higher percentage of children in the experimental group were accurate in their reports than the other groups. Results from pre- and posttests showed that the children in the experimental group wrote more specific and relevant comments when reporting their reflections and had better language performance. Implications for practice and recommendations for future research are discussed.