Public school students do not surrender their rights at the entrance, and schools hold real authority over conduct. Dress codes are where those two facts meet most often.
The framework balances expression against disruption
Courts have long recognized that students retain expressive rights in public schools, while allowing schools to restrict expression that would substantially disrupt the educational environment.
Applying that standard requires judgment about a specific item in a specific school, which is why outcomes differ and why general statements about what is allowed are unreliable.
The framework also distinguishes between expression that carries a message and clothing choices that do not, and the analysis is not the same for both.
Enforcement is where most disputes actually arise
A policy applied evenly to all students raises different questions than a policy written neutrally and enforced unevenly by body type, gender or which students are noticed.
Because enforcement is discretionary and happens in hallways rather than in writing, the pattern only becomes visible when someone records who is stopped and for what.
Removal from class as a penalty carries an additional consequence, since a dress code violation then costs instructional time, which is a separate matter from the rule itself.
Several distinct legal questions overlap
Rules touching religious dress, hair texture and protective styles, and treatment based on sex or gender each engage different statutes and different protections.
A number of states have enacted laws addressing hair-based discrimination specifically, and coverage differs by state, which means identical policies can be lawful in one place and not another.
Private schools operate differently
Constitutional constraints apply to government actors, so private institutions generally set dress policy under a contractual relationship with families rather than under the same framework.
Charter schools occupy a more complicated position that depends on state law and how the school is constituted, which is a question for a local education attorney.
The practical route runs through policy first
Districts publish dress codes and grievance procedures, and a written objection through that procedure creates a record and often resolves the matter without escalation.
Rules in this area vary by state and district and are revised frequently, so anyone contesting a specific decision should consult a civil liberties organization or an attorney experienced in education law.
Students changing a policy have more often done it through school board processes than through litigation, which is slower in appearance and frequently faster in practice.