* Distract you from studies: If you're constantly worrying about behavioral issues, it can impact your focus in class and on homework.
* Lead to further disciplinary actions: Repeated detentions might result in more serious consequences that *do* impact your grades, such as suspension or removal from certain classes or activities.
* Signal a larger problem: Many detentions often point to underlying issues (like lack of sleep, home problems, or learning difficulties) that could negatively affect your academics.
In short, one detention is unlikely to change your grade, but a pattern of disciplinary actions might have an indirect impact.