<P> The schools that do require uniforms, or a more common standard dress code in towns and suburbs, tend to be more casual than those in Britain or other commonwealth nations . Commonly, students wear collared, buttoned shirts, with a tie for boys and a tie for girls, worn with khaki trousers, and a belt, depending on the age of the school's student body . Skirts of a modest length are occasionally an option for girls . </P> <P> For instance, red, white or blue polo shirts, with a logo, with navy or khaki bottoms and a belt, was the uniform policy imposed at Palmer Elementary School in Houston, Texas . Schools may also have polo shirts and trousers as a uniform . Dress codes vary widely among private schools, although a Catholic school uniform tends to keep the shirt and tie . </P> <P> As of August 2013, almost one fifth of all American schools required their students to wear uniforms (Flam). This 20 percent of schools requiring uniforms is six percent higher than in 2003, the U.S. Department of Education reported . The uniform requirement is more common in lower socio - economic schools, where more than three - fourths of the school's student population receives free or reduced lunch ("Fast"). Forty - seven percent of low income schools require uniforms, whereas only about six percent of high socio - economic schools require uniforms ("Fast"). </P> <P> The National Association of Elementary School Principals (NAESP) conducted a phone survey of 755 principals in 2000, which revealed that 21% of public schools had a uniform policy; 23% had firm plans to create one . However, this only accounts for those with school uniform policies and not for standardised dress codes, which provide for allowable student dress but are slightly more lax: For instance, instead of requiring everyone to wear the same shirt, or set of shirts, they may specify "any solid collared three - button polo / oxford shirt" and leave more specific details up to the parents . In 2007 - 2008, 55% of public school principals said their schools enforce a strict dress code, requiring students at least wear a collared shirt and trousers with an acceptable belt to school . </P>

What is the percentage of schools that wear uniforms
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