（穿著）校服可以减少同侪压力，和使学生之间的阶级分别变得不明显。
这句的意思是说：学生穿校服，大家穿著都一样，就不用互相攀比。
class 在这里是指阶级，如富有、贫穷等。
~~~~~~~~纯人手翻译，欢迎采纳~~~~~~~~~
这一句的上文如下：
Uniforms create a level playing field. When all students are dressed alike, competition between students over clothing choices and the teasing of those who are dressed in less expensive or less fashionable outfits can be eliminated. In a 2013 survey by the National Association of Elementary School Principals (NAESP) and uniform manufacturer Lands' End, 86% of school leaders said uniforms make "a significant, positive impact on peer pressure," and 64% said uniforms reduce bullying. Arminta Jacobson, Founder and Director of the Center for Parent Education at the University of North Texas, stated that uniforms put "all kids on the same playing field in terms of their appearance. I think it probably gives them a sense of belonging and a feeling of being socially accepted." Virginia B. Draa, Assistant Professor of Human Ecology at Youngstown State University, said uniforms can decrease peer pressure and blur class lines between students.
