Philadelphia has become the first major city in the United States to order all of its pupils to wear school uniforms.

The city's school district board has ruled that all 217,000 pupils in the city's 256 schools must now wear uniforms.

Choosing the uniforms has been left up to individual schools, but officials said schools would be encouraged to consider clothes that were inexpensive and readily available.

The decision followed a request for the Philadelphia school district board to consider the issue of uniforms by the Mayor, John Street.

A study by the National Association of Elementary School Principals in 1998 found that 52% of principals at schools requiring pupils to wear uniforms reported a boost in student performance.

Respect

Philadelphia school district board member Christine James-Brown said that making pupils wear uniforms was "not the answer to academic achievement or school climate".

But she said: "I think it can be one component to establishing respect for the school."

School dress code policies have been endorsed by the US President, Bill Clinton, and other cities have uniform policies.

In Chicago, 80% of public schools require students to wear uniforms. The figure is 60% in Miami. But no city as large as Philadelphia has a district-wide policy.

Opposition

Before the Philadelphia school district board voted on the issue, it heard from about a dozen parents and students who were against the compulsory introduction of uniforms.

Mother-of-two Lisa Haver said: "We need to be dealing with kids who cannot read or write. People who make suggestions like this are people who don't spend any time in school."

High school senior Adam Greenman said a uniform policy would give students another way to get into trouble, and predicted widespread opposition to the dress code.

"If you implement this policy, student who once were considered goo might now be considered discipline problems.

"We were made to be different, we were not made to be uniform."