High School Principal Says All Girls' Prom Dresses Must Be Pre-Approved

A high school principal in Louisiana is requesting the students to text her a picture of their prom dress, to make sure it adheres to the rules of what's considered "appropriate attire", including being too sheer or revealing.

When I was in high school, 100 years ago, we only went to the prom to get the pictures taken, then we all left, and went to a house party or whatever, which also meant we quickly changed back into normal everyday clothes. I guess that's what I get for living in a small town. I guess this principal is in fear that prom will turn into more of a shock fashion-show type event, and wants to closely monitor the outfits.

Wow, parents, students, what do you think about this? Is it too controlling? Is it reasonable?