This study investigated the mediating effects of learning a memory strategy on second-graders' performance of a memory task and their self-efficacy for the task. Specifically, second-graders were taught a strategy for organizing words into categories to increase their ability to remember lists of words. Their predictions of how many words they would subsequently remember were taken as a measure of self-efficacy for the task. The trained students not only outperformed their untrained counterparts on the memory task, but also predicted higher levels of future performance, indicating that their efficacy for the task had increased. Quantitative data were collected to measure students' predictions and performance, while qualitative data provided insight into students' strategy use and ability to articulate their actions.