But the fun begins in the comments. And after reading them, I'm inclined to support the school. The point of school is to help students become productive adults, able to walk into job interviews outside of their own small community: and one of the skills is learning to present yourself well (and yes, that includes cutting your hair and dressing nicely -- to arrive otherwise suggests to the employer that you are someone who has to be worked around rather than worked with -- and who hires them?).
Learning simple things can make job interviews go much more smoothly. Admittedly, there are jobs where how you dress makes almost no difference. Ditch digger, for example. And if you aspire to that job, there are openings, unlike "unsuccessful guitar player for front band".
UPDATE: Comments are getting interesting. Click through.