I agree with school uniform because of many reasons.
First of all, if you wear casual in school, you will have to buy many clothes. In addition, you will be nervous about other student's brand clothes. It's very burden on your parents.
Secondly, wearing school uniform can make bond between many students. School have to teach cooperation to students and the best way to teach that is to make them wear school uniform.
Thirdly, when students wear their uniforms, they don't become delinquent. In other word, they act like good students because the uniform remind their schools proud.
So I agree with wearing uniform