I worked for an Elementery School for a time in 2004, and let me tell you, dress codes and uniforms aren't there cause OMFG BIG BAD GOVERNMENTS WANTS US TO SPEND MONEY! it's because a majority of parents agreed with it.
when I was most of yall's ages, I hated my dress code. I thought it was stupid and served no purpose. But really, I was stupid. Baggy pants not only make you trip, other people trip on them. Wallet chains can and were used as weapons in my high school. You don't wear hats or bandanas to formal gatherings, don't wear them to school. There is no reason any student needs a knife, gun, drugs, etc., much less on school property.
Uniforms are a great idea. Someone mentioned the issue of "kids get picked on if they aren't wearing the clothes that are 'in'" and you have an excellent point. I know when I was in elementery school, I always got made fun of for not wearing expensive clothes. I noticed once my parents got into some money when I hit high school, and I could afford the more expensive clothes I wanted (I was a hot topic loser haha), no one made comments about the price of my clothing. So yes, it is an issue, everywhere. Since parents are too lazy to instill into their children that just because someone isn't wearing Prada shoes doesn't mean their worth amounts to nothing, we will have this issue. Thus, a uniform is a great idea. You will have no goths/punks/losers/nerds/geeks/preps/whatever the heck you people call each other nowadays. Everyone will be dressed the same. It's easier to make friends and get along if this is done from Kindergarten on up.
A lot of parents came to me with issues on their child's dress code. I remember busting one little girl for wearing a mini skirt and a shirt that revealed her entire back and stomach. There is a reason that is not allowed. What kind of family would dress their daughter in that knowing boys and men are around is beyond me, but that's exactly the reason. Health and safey issues play another role. Sorry, but spiked bracelets can cut through skin. You can use those just as easily as a blunt object or knife to get to someone.
Someone mentioned uniforms being expensive...that's one I've never heard before. I know when I lived in Florida, uniforms were cheaper than department store clothing, and you bought them in department stores, depending on the school you went to (some you had to have an emblem on, but these schools are generally expensive to begin with).