Uniforms should be allowed in school

Uniforms should be allowed in school for the three contentions stated below
My first contention is that schools need to have uniforms to instill good discipline in students. It makes students look professional and forces them to take good care of their uniform as if it were their work clothes. When students are forced to take responsibility of how they look they look more professional. When students dress professionally and conservatively they tend to be more focused in school and perform better.

My second main contention is that students are more focused resulting in higher grades and here are my sources to back up my claim. Here are a couple articles reporting on studies showing how attendance records and graduation rates improved (http://www.woio.com......) (http://findarticles.com......) Here is a list of which countries perform the best in mathematics. (http://nces.ed.gov......)
The top 5 countries in 8th grade math are, in order Taiwan, South Korea, Singapore, Honk Kong, and Japan. All of these countries have school uniforms.

My third main contention is that there is the cost of common articles of clothing that compose a typical school uniform.
(http://www.target.com......)Boys Shirt $8, (http://www.target.com......) Boys shorts 3-5$, Boys long pants 14$

Wal-Mart, known for their extraordinarily low prices sells polo shirts for 6$ each.
(http://www.walmart.com......) Wal-mart t-shirts barely beat the prices that major national retail outlets charge for school uniforms. This is even assuming that most students buy their clothes from Wal-Mart, which they don't. They buy from Abercrombie, American eagle, Hollister, which sell simple T-shirts for as much as 20$
Hollister prices for simple T-shirts (http://www.hollisterco.com......)
Americans are well off and paying on average 8$ for a uniform shirt is not unreasonable.