When I was a student - I never attended a school with uniforms. None of my schools had significant issues from dress and appearance problems, so I don't see what it would have changed.
As a parent of four students - for a time we were in a uniformed school district. It was a pain, actually. Some areas might be more considerate than others - but buying uniforms is far more costly because schools made it very complicated.
My kids had this:
No polyester. Boys wore a belt. Tops had to be dark blue, red, or yellow proper shirts (no t-shirts or tank tops but things like polos and button-ups). Shoes had to be only from a select few styles.
1) Not all places sold school-appropriate articles of clothing. Where they did - it was often marked much higher. I can find t-shirts for a few bucks but when it comes to uniforms, everything was between $5.00 - $12.00 a top and pants were higher.
2) Limited materials - by disallowing polyesters and knits they limited the available selection which forced me to buy more expensive articles if the cheaper one was the wrong material.
3) Shoes - dress shoes were more expensive. Aside that, kids spend time running around in the dirt and rain while at school, dress shoes are just thoughtless and inappropriate. They are ruined more quickly and much more expensive to replace.
4) Belts - my oldest was in K-2, special needs, and always needed help with his belt. It was entirely ridiculous for them to require it. They complained to me often, though they're the ones who decided that the button-shirt line had to fall in line with the pants and be topped off with a belt. The only thing missing was a tie :roll:
5) Heat - we live in Arkansas. A few months of every school year it's too hot for pants and sleeved tops (upper 90's and 100's with high humidity), yet they required them - kids were more uncomfortable.
6) Color choices and children - light colors like yellow, light blue, khaki and beige are horrible choices for school clothing. Kids go to school where they use paint, glue, and drink chocolate milk. I had a lot of clothing go to the trash because they quickly became stained and the stains would not come out - especially the paint.
We were dirt poor - and hunting down uniformed articles was a pain in the butt. It's inconsiderate to put people in that type of situation and it solved nothing. I ended up finding long sleeve shirts and clothes that were too big at good-will and then taking them in so they'd fit. Dressing kids should not be so difficult to tedious.
All in all - it cost us hundreds more every single year, created faux problems like the teachers complaining my special needs son needed too much help (tying shoes and lacing his belt), and on top of that - you still have to cloth the child in regular clothes like t-shirts and shorts so they can go out side and play.
It also increased laundry time by almost doubling the dirty clothes you had to wash each month.
All in all - it was a pointless pain in my butt and thus - I oppose them strongly. Most people are not well off nor do they have time to keep after it all.
Sometimes crap happened - like one week (we lived in an apartment) and the laundromat dryer system stopped working - we didn't have clean clothes for school, they wore regular clothes - and I was given a hard time for it.