Sometimes, deciding the best is difficult.

　　For example, deciding the 10 best public high schools – out of 24,000 – in America.

　　Two publications put together lists of the top 10. But the website Niche.com and the magazine U.S. News and World Report could agree on only one.

　　Both named Thomas Jefferson High School for Science & Technology of Fairfax County, Virginia. Many people call it just "Thomas Jefferson."

　　Niche ranked Thomas Jefferson number four. U.S. News put Thomas Jefferson at six.

　　But the two publications could not agree on their other top nine high schools.

　　Chicago has it?

　　In Niche.com's latest ratings, three of the top public high schools are located in Chicago, Illinois, America's third most populated city.

　　The Chicago schools are Walter Payton College Prep, rated Number 1; Northside College Preparatory High School, Number 2; and Young Magnet High School, Number 6.

　　The top ratings for Chicago schools come at a time when violence among young people remains a problem. Chicago Mayor Rahm Emanuel welcomed the good news for his city.

　　"I am so proud of the great work by principals, teachers and students in these high schools," Emanuel said.

　　Or do charter schools?

　　In contrast, U.S. News and World Report gave its top ratings to charter schools. Charter schools receive public money, but operate independently of many local and state education rules.

　　Three charter schools in Arizona took the highest positions at U.S. News and World Report. They are all operated by a private company called BASIS Education Group LLC. BASIS also operates charter schools in Texas, Louisiana and Washington D.C.

　　The BASIS school in Scottsdale, Arizona was rated Number 1 nationally, followed by BASIS Tucson North and BASIS Oro Valley.

　　Another BASIS Arizona charter, BASIS Peoria, was ranked Number 5.

　　U.S. News said it made a change in its ratings this year, giving more weight to high schools where students take and pass college-level courses and exams. Preparing high school students for college-level classes and tests is a major part of BASIS' education plan for its students.

　　Robert Morse worked on the best high school rating system. He said that U.S. News wanted to give credit to schools that "that make an effort to challenge their students."

　　How should parents look at school ratings?

　　Laura Owen is director of the American University School of Education's Center for Postsecondary Readiness and Success. She said that all schools want to be rated highly.

　　But just because a school is ranked highly does not mean it is the best school for every child, Owen said. Parents have to decide which schools offer the academics and support that will help their children learn and reach their potential.

　　Elise Hauptman has two children at Stevenson High School in Illinois, the number-three rated public high school according to Niche.com.

　　She said Stevenson does something many schools fail to do: make changes to meet the needs of current students.

　　"They were among the first in the area to delay the start time of the school day, acknowledging sleep studies done on teens," Hauptman said. "The day starts half an hour later, but both of my kids said it makes a huge difference."

　　She also points to the school's willingness to meet the needs of a variety of students -- not just those with the highest grades. Their efforts include adding new subjects, such as "writing for college," and starting a new club to deal with drug and alcohol abuse.

　　How did the publications rank the best high schools?

　　When considering rankings, U.S. News said it looks at whether a school's students do better than expected on reading and math tests. U.S. News also says that it looks at how "disadvantaged students," including black and Hispanic students, perform on tests.

　　Niche says it bases its ratings on students' performance on standardized tests, racial and economic diversity of the school population, and comments from a school's students and their parents.

　　Six of the ten top high schools rated by Niche.com select their students. That means they can choose the brightest middle and junior high school students for their schools.

　　But the BASIS schools in Arizona that scored so high in the U.S. News and World Report's ratings do not have admission requirements. School officials say they hold a lottery when they have more students than they can accept.

　　Kristen Jordison is Head of School at BASIS Scottsdale, which was ranked Number 1 in the latest U.S. News and World Report survey.

　　She said the school is successful because it has excellent teachers and demands a lot of students, including college-level assignments.

　　"Our students and teachers work very hard," Jordison said.

　　Teachers and fellow students work with children individually who are struggling with classes, Jordison said.

　　Audrey Amrein-Beardsley is a professor at Arizona State University's Mary Lou Fulton Teachers College.

　　She said that BASIS schools in Arizona are open to everyone. But by not offering transportation and free lunch programs, the schools can be difficult for low-income parents to send their children to, Amrein-Beardsley said. The result is that BASIS schools take in fewer minority students and fewer students from poor families than regular public schools, she said.

　　Joe Thomas is president of the Arizona Education Association, a union that represents the state's public school teachers.

　　Thomas said that every school, public or private, will lose students each year. But he said that BASIS schools lose a lot more students than other schools because not all students are ready to take college-level classes.

　　I'm Bruce Alpert.

　　And I'm Jill Robbins.

　　Bruce Alpert reported on this story for Learning English. Kelly Jean Kelly was the editor.

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