Most high school students in the country carry a smartphone, making it the single most unifying characteristic of adolescence today. These devices are so normalized that many students never consider how proximity alone might quietly undermine their ability to learn. Yet a growing body of research points to a phenomenon known as the brain drain effect, where the mere presence of a personal smartphone occupies limited cognitive resources and reduces available working memory, even when the device is silenced, face-down, and never checked. Despite mounting evidence in university populations, this effect remains critically understudied among high school students, who are arguably the most device-dependent and developmentally vulnerable demographic. This exploratory study investigates whether the mere presence or smartphones impair retention of academic material in high school students at BASIS Independent Brooklyn. Using a two-condition between-subjects design, 45 to 60 participants across multiple grade levels complete a standardized recall task either with their phone placed visibly on the desk or stored in a separate room. By sampling across grades, the study also examines whether developmental stage during puberty, a period of rapid cognitive and neurological growth, moderates the strength of the brain drain effect. The ultimate goal of this research is not simply to document a problem but to empower students with actionable knowledge about their own learning. Armed with evidence about how phone proximity shapes academic performance, students will gain the ability to control their learning conditions, deepen their comprehension, and ultimately enjoy a more meaningful educational experience.