* School rules: Many high schools have dress codes that prohibit unnatural hair colors. Some might be more lenient than others. You need to check your school's student handbook or contact the administration directly to find out their specific policy.
* Parental permission: Even if the school allows it, you'll likely need your parents' permission, especially if you're a minor. They may have concerns about the chemicals used in hair dye or the potential damage to your hair.
* Age: In some jurisdictions, minors might need parental consent to receive certain services, including hair dyeing at a salon.
In short, there's no universal answer. You must check your school's rules and obtain the necessary parental permission before dyeing your hair.