Wear The Appropriate Uniform

You don't get to decide *which* uniform you wear at functions; whoever is putting on the function decides the uniform. And if the uniform for graduation is school cap and gown, then that's what it is--Marine or not:

"Once a Marine, always a Marine" apparently doesn't apply at a Pennsylvania high school where a 17-year-old graduate has been told she cannot wear her uniform when she receives her diploma.

Lindsay Starr told KDKA-TV in Pittsburgh she wanted to wear her dress blues during Friday's graduation ceremony at North Allegheny High School in Pittsburgh, but that school officials denied her request, citing the requirement of wearing only the traditional cap and gown.

I would think that the Marines would have taught her more about being part of the team and less about trying to bring more attention to yourself.