High School Physics and the Challenge Index

Susan White

Since 1998, Newsweek and The Washington Post have calculated Challenge Index (CI) ratings for US high schools. The Challenge Index is calculated by taking the total number of Advanced Placement, International Baccalaureate or Cambridge tests given at a school in May and dividing by the number of seniors graduating in May or June. Schools with a CI of at least 1 are included in the Challenge Index list. A CI of at least 1 means that a school gave as many advanced tests as it had graduates; this list, then, represents schools that challenge their students across the curriculum to prepare for college. About 5% of US high schools have a CI of 1 or higher.

Is there any evidence of a relationship between physics in the high school and broader academic challenge, as reflected by advanced test taking in all subjects? We examine physics at high schools that were included on both the 2007 and 2008 lists in order to answer that question.

We identified 1,137 schools that appeared on both the 2007 and 2008 Challenge Index lists. We then compared those schools with the 3,447 schools in our representative national sample of US high schools for which we have data about the number of teachers teaching physics in 2005. There are 152 schools that appear on both lists.

The difference between the distribution of teachers teaching physics at the schools with a CI of 1 or higher and the distribution at all US high schools is striking and is shown in the figure below.

Number of Teachers Teaching Physics: 2005

1 While these data seem to indicate that about 18% of US high schools do not offer physics at all, it should be noted that some schools offer it only in alternating years and are represented by a 0 here because 2005 was a "no physics" year.
Source: AIP Statistical Research Center: 2004-05 High School Physics Survey & Newsweek/Washington Post Challenge Index

While less than 3% of all US high schools have 4 or more teachers teaching physics in a typical year, over 20% of the high CI schools fall into this category. In fact, the proportion of high CI schools with 4 or more teachers teaching physics is almost 8 times higher than that of all US high schools. Multiple teachers teaching physics indicates larger enrollments in physics at these schools. Even though 89% of US high schools, serving 97% of the students, offer physics regularly, more than 80% of these schools have only one teacher teaching it; the opposite is true for high CI schools with over 70% of the high CI schools having more than one physics teacher.

Certainly the CI is an imperfect measure in trying to determine the "best" or "top" high schools. It does not include pass rates on the exams, and it does not account for differences in the underlying student populations which affect the number of students taking exams. The list is incomplete since there is no national database that includes the required data; schools that believe they qualify with an index of 1 or higher are invited to submit data after publication. Furthermore, a group of 38 school superintendents from five states requested that their schools not be included in the 2008 list.

At the same time, the CI does provide quantitative information about what is happening in US high schools. Jay Mathews, Education reporter at The Washington Post and creator of the Challenge Index, reports that schools on the list "turn out to have principals and teachers who are trying hardest to raise the achievement of each child, with college as a useful goal for all." As the US struggles to reinvigorate interest, enrollments, and diversity in science, technology, engineering, and mathematics (STEM) disciplines, it is important to note the high correlation between having two or more teachers teaching physics and achievement as measured by the Challenge Index. Furthermore, these data suggest that a vital high school physics program is a fundamental part of the recipe to challenge students in all fields.

Susan White is a member of the Statistical Research Center of the American Institute of Physics

This article is not peer refereed and represents solely the views of the author and not necessarily the views of APS.