I have a majorly strict dress code. We have to wear either a blue or white polo (with school logo), a white oxford, or a white midi blouse (think Sailor Moon for that shirt), with a plaid skirt, as our regular uniform. On Eucharist days, we have to wear a plaid jumper that fits an eight-year-old better than it does an eighteen-year-old, with a white oxford or white midi shirt. Jackets MUST be bought at the school store. Patterned or non-white/navy blue/black/grey tights are not allowed. If you're in lower school, you aren't allowed to wear anything but tennis shoes (I do not miss those days). Girls aren't allowed to wear pants unless it's cold. (And even if it's freezing cold, ie, Snowmageddon of the South, we don't get to wear non-school jackets...)
This leads to wondering how on earth you can show your individuality at school, especially when your skirts even have a regulation length (at least two inches above the knee, for me). My solution is to go for the shoes, the hair, and jewelry.
My necklace collection makes frequent appearances at school, as does my gold cuff bracelet. I usually go for flats, but I finally gave in to the part of my brain that has been screeching about boots since I stopped wearing them last year, and pulled out the tights. It's still, technically, too hot for tights in Texas, but I justified it with the fact that all my classrooms are freezing. Another thing that helps is tailoring (though I haven't really bothered with most of my things for school...), and, if you've got something as open-ended as 'white oxford' finding something that flatters you. (I'm still looking for that, as you can tell - I could use tips on how to buy button downs while having a large chest!) Find a non-traditional hairstyle you look good with, get proficient at it, and you will stand out sooo much.
I hope this helps anyone out there who struggles with their dress code.