A strong high school education can provide a foundation that will help graduates enter the world ready for college or a career.

The difference between finishing high school and dropping out can be measured financially. According to the National Center for Education Statistics, which looked at 2017 Census Bureau population survey data for full-time working adults ages 25 to 34, high school graduates earned an average of $32,000 a year compared with $26,000 for those who did not earn a diploma. Measured over a lifetime, the difference between graduating from high school and dropping out can add up to hundreds of thousands of dollars. Likewise, the data noted that those who went on to earn a two-year degree or at least a bachelor's degree earned an average of $39,000 and $55,000 a year, respectively.

Graduation rates and college readiness, both key factors for the path to a higher education, are among the many metrics U.S. News used to determine the 2020 Best High Schools, released today. U.S. News ranked approximately 17,790 public high schools, out of a review of more than 24,000 in all 50 states and the District of Columbia; the number of ranked schools is up by more than 500 from last year. U.S. News coordinated with North Carolina-based RTI International, a global nonprofit social science research firm, to rank the 2020 Best High Schools.

The ranking methodology draws from data for the 2017-2018 school year, using both state and federal datasets. In addition, the College Board and International Baccalaureate provided data on their respective college-prep programs, Advanced Placement and IB. These are the six indicators of school quality used to calculate the rankings:

College readiness, based on the proportions of 12th grade students who took and passed AP and/or IB exams.

College curriculum breadth, based on proportions of 12th grade students who took and passed AP and/or IB exams in multiple content areas.

Math and reading proficiency, based on student performance on state-required tests.

Math and reading performance, based on whether performance on state assessments exceeded expectations given the school's proportion of underserved students.

Underserved student performance, based on how black, Hispanic and low-income students performed on state assessments compared with those who are not underserved in the state.

Graduation rates, based on the proportion of students who entered ninth grade in 2013-2014 and graduated four years later.

The highest-ranked schools are those whose students excelled on state tests and performed beyond expectations; participated in and passed a variety of college-level exams; and graduated in high proportions. U.S. News assigned numerical ranks to schools performing in the top 75%. Schools performing below the 25th percentile are listed alphabetically with a ranking range.

Thomas Jefferson High School for Science and Technology in Virginia claimed the top spot in this year's Best High Schools rankings, with an overall score of 100. Last year's No. 1, Academic Magnet High School in South Carolina, slipped to No. 2 in the new rankings.

Rounding out the rest of the top 10 of the national rankings, in order, are: Merrol Hyde Magnet School in Tennessee, School for Advanced Studies in Miami, Townsend Harris High School in New York, The School for the Talented and Gifted in Dallas, BASIS Chandler in Arizona, Haas Hall Academy Bentonville in Arkansas, Payton College Preparatory High School in Chicago and Irma Lerma Rangel Young Women's Leadership School in Dallas.

Of the 10 geographically diverse schools represented here, seven were not in the top 10 last year.

Additionally, U.S. News ranked the top magnet schools and charter schools separately based on how these schools performed in the national rankings.

Magnets are public schools with a thematic curriculum often tied to the STEM fields of science, technology, engineering and math; fine arts; career and technical education; or other areas of study. Students are typically admitted to magnet schools through a lottery system. Charter schools are also public, though independently operated, which means greater autonomy over curriculum and exemption from some state laws and regulations.

The No. 1 school overall, Thomas Jefferson High School for Science and Technology, also claims the top spot among magnet schools. The top charter school is BASIS Chandler in Arizona, which came in at No. 7 in the overall rankings.

Among all schools ranked nationally, 10.6% are charters and 5.2% are magnets.

U.S. News also ranked the Best High Schools for STEM, with an emphasis on AP science and math test results. Of the 250 schools on this list, all were required to be in the top 1,000 of the overall national rankings to be eligible.

Like last year, the top STEM school for 2020 is High Technology High School in New Jersey, which ranked No. 57 overall. Of the top 10 schools in the overall rankings, only three also made the top 10 in the STEM rankings: Thomas Jefferson High School for Science and Technology at No. 3, BASIS Chandler at No. 6 and The School for the Talented and Gifted at No. 9.

Overall, state performance in the 2020 Best High Schools rankings varies. Texas, for example, is the only state to have two schools in the top 10. The Lone Star State has 11 schools in the top 100, tied with Arizona, California and New York for the most schools in the top 100 of any states.

Looking beyond the top 100, however, Massachusetts once again comes out on top when compared with other states on the largest proportion of schools in the top 25% of the Best High Schools rankings. Nearly 50% of eligible high schools from the Bay State are represented in the top quarter of the national rankings. California comes in second, with about 41% of its schools in the top quarter, followed by Connecticut in third with around 40%.

U.S. News also ranked high schools by metropolitan area. For a school to be eligible for these rankings, a metropolitan area must have three or more high schools in the national rankings, a change from 2019 when the minimum requirement was one ranked school.

When looking at which metro areas have the largest proportion of schools in the top 25% of the national rankings, San Jose, California, tops the list, with 40 of 63 high schools in the top quarter.

For the first time, U.S. News also ranked schools by school district for those that have three or more high schools; a school's district rank is based on its performance in the overall national rankings.