Learning and Understanding: Improving Advanced Study of Mathematics and Science in U.S. High Schools: Report of the Content Panel for Chemistry (2002)

In addition to recommending that at least 290 minutes per week be allotted to AP Chemistry courses, the College Board characterizes the AP Chemistry course as follows:

Thus by design, AP Chemistry courses (and all other AP courses) are modeled after typical college-level introductory courses in the discipline. As a result, these high school courses are supposed to follow trends in college-level introductory general chemistry (not introductory chemistry, which typically denotes remedial or non–science major chemistry courses).

Whether schools offering AP courses follow this recommendation probably depends on local practice. In any case, the chemistry panel unanimously agrees that, unless truly exceptional circumstances dictate, students should not take advanced chemistry as their first chemistry course in high school.⁴ Although the College Board also recommends against this practice, it does happen, and the panel believes it is detrimental to the student, who is academically short-changed by such circumstances. It is in the first course that the requisite concepts are learned and the laboratory skills developed that are needed to legitimize advanced study in the second high school chemistry course.⁵

An appropriate background in mathematics is needed to succeed in AP Chemistry, and the College Board addresses this matter as well: “In addition, the recommended mathematics prerequisite for an AP Chemistry class is the successful completion of a second-year algebra course” (CEEB, 1999a, p. 1) (Note: Italics added for emphasis by the College Board.)

The College Board also is explicit regarding the place of AP Chemistry in the total science curriculum: “The advanced work in chemistry should not displace any other part of the student’s science curriculum. It is highly desirable that a student have a course in secondary school physics and a four-year college preparatory program in mathematics” (CEEB, 1999a, p. 2).

Because of the structure of the AP program, the AP Chemistry course can be a standalone course offered by a high school in the absence of any other AP course offerings at that high school or other high schools in the district. Moreover, students who enroll in and complete AP

Chemistry, or any other AP courses, are not required by the College Board to take the AP examination developed by the College Board and administered by the Educational Testing Service.⁶

Administered each May, the AP Chemistry examination is 3-hour examination consisting of 2 sections. The first section (90 minutes) consists of 75 multiple-choice questions and represents 45 percent of the final grade. The College Board uses some common multiple-choice questions from year to year as a consistency check on the performance of the students taking the exam. The second section of the examination (also 90 minutes) represents 55 percent of the final grade and consists of several short-answer and essay-style questions that purportedly provide for a more in-depth assessment of students’ understanding of chemical principles. The questions may require calculations, a short essay response, or the determination of reaction products. Section II contains both required questions to which all students must respond and opportunities for students to choose two of four additional questions that they think they are best prepared to answer.⁷ The examinations are collected and sent to a central location, where they are graded by a national team of graders.⁸ All of the examinations are graded during a 1-week period. The College Board has developed procedures to ensure uniformity in the scoring process.⁹ The AP score (1–5) is determined by a complex formula that factors in how well others who took the test performed, how scores were distributed over the past 3 years, and how well college students at the end of their introductory course performed on the AP examination.

Whereas the AP program is a collection of individual, unrelated courses, the International Baccalaureate Diploma Programme is a comprehensive 2-year curriculum consisting of six academic areas.¹⁰ IB courses may be taken at either the Standard Level (SL) or Higher Level (HL).¹¹ Chemistry is included with Group 4, the Experimental Sciences. IB Diploma candidates must take one subject from each of the six subject areas, with at least three and not more than

four being HL. The other courses taken are SL. Thus, a chemistry student can take either the HL or SL version of the IB Chemistry course and related examination. IB students are permitted to take two science subjects simultaneously from Group 4.

Students can and do take individual IB courses without working toward an IB Diploma. These students are known as certificate candidates, as opposed to diploma candidates. Only diploma candidates are required to take one subject from each area, as well as to fulfill additional requirements. Approximately 65 percent of IB students work for and complete the requirements for a diploma.

IB Diploma candidates must also complete three other requirements: (1) the interdisciplinary Theory of Knowledge course; (2) an extended essay of approximately 4000 words; and (3) participation in the school’s Creativity, Action, Service (CAS) program involving sports, artistic pursuits, and community service work. Unlike the AP program, the IB program seeks to provide interdisciplinary preparation for university work rather than attempting to meet particular university course requirements, although strong performance in IB courses is used to grant advanced placement at colleges and universities (International Baccalaureate Organisation [IBO], 1999).

All Group 4 subjects include required practical (laboratory) work, which makes up a significant portion of the course.¹² Although this laboratory work focuses primarily on the assessment of laboratory skills, it also offers opportunities for students to perform experiments and experience first-hand the benefits and limitations of scientific methodology. Individual teachers plan the Practical Scheme of Work (PSOW) for students in their classes. Thus, the laboratory experiences of students in different IB classrooms will vary. The PSOW should represent the breadth and depth of the subject syllabus, but students are not required to conduct an investigation for each topic in the syllabus. To ensure quality and to foster improvements, teachers are required to submit copies of their PSOW annually to the IBO for moderation and feedback.

As noted above, the College Board recommends that at least 290 minutes per week be allotted for an AP chemistry class (174 total hours per year, assuming a 36-week academic year). Of this total, 54 hours is recommended for laboratory work. By comparison, IB recommends a total of 240 hours for HL and 150 hours for SL courses per academic year. Of this time, it is recommended that 60 hours for HL courses and 40 hours for SL courses be devoted to investigative activities that, along with the Group 4 project, comprise the internal assessment (IA) component of the course.

A common core curriculum applies to both HL and SL chemistry courses. The core material taken by SL students is a subset of the HL program. At the SL level, the core topics make up about 60 percent of the material, while at the HL level the core represents 75 percent of the covered topics. Both SL and HL students also study optional topics that their teacher selects from among a list of topics included in the course syllabus. SL students study three options of 20 hours each, while HL students study two options of 30 hours each chosen by the school. The only option available exclusively to SL students is higher physical organic chemistry (15 hours).

Options available to both SL and HL students (15 and 22 hours, respectively) include medicines and drugs, human biochemistry, environmental chemistry, chemical industries, and fuels and energy. The options available to HL students only (22 hours) are modern analytical chemistry and further organic chemistry. Additional hours of internally assessed practical work are required for both SL and HL options.¹³ Further, both SL and HL students must spend 10–15 hours on an interdisciplinary Group 4 project, which is a common element of all IB science programs and constitutes 10 hours of the internally assessed practical scheme of work.¹⁴

The IB Chemistry examination is given annually and is taken at either the SL or HL, depending on the student’s course of study. The SL exam consists of three papers. The first paper (0.75 hour) consists of 30 multiple-choice questions. The second paper (1 hour) contains short-answer questions and brief calculations in Part A and offers students a choice of answering one of two more-extended questions in Part B. The remaining paper (1.25 hours) consists of one or two questions based on the course options completed by an individual student. The HL examination also comprises three papers with the same distribution as that of the SL examination, but with topics examined in greater depth. The time allotted for the first HL paper is 1 hour, for the second 2.25 hours, and for the third 1.25 hours.

IB examinations are sent to examiners around the world who mark and return them to the IBO offices in Cardiff, Wales. During the grading process, examiners measure each student’s performance against seven grade descriptors, given in the form of levels of performance that candidates can demonstrate on the examination. To ensure uniformity in the grading across examiners who are not centrally located, a representative sample of graded examinations from individual examiners is sent to the chief examiner for moderation. IB examination grades (1–7) are based on established criteria that represent an absolute standard of quality; thus, the interpretation of a student’s performance is criterion-referenced. A grade of 7 represents “excellent performance,” while grades of 4 and 1 represent “satisfactory” and “very poor” performance, respectively. All IB group subjects, including chemistry, have a significant IA component involving laboratory work and a project, which constitutes 24 percent of a student’s final grade. The IA component is internally assessed at the student’s school by the teacher and is also externally moderated by the IBO. Final IB scores for each student are a combination of the results of the IA and the external scoring of the examination papers, but are reported to the school as a single total.

To provide a chemistry course consistent with the criteria noted above for an advanced study course in chemistry at the high school level, those who teach such a course must be adequately prepared. The chemistry panel takes this to mean a B.S. or B.A. degree in chemistry, and preferably an M.A. or M.S. degree in chemistry. The preparation of AP and IB Chemistry teachers is discussed in detail in Chapter 4.

The chemistry panel agrees that the prerequisite first-year high school course in chemistry should provide students with an introduction to the atomic-scale view of matter, including its connection to macroscopic physical and chemical properties and to the language used to express these relationships, using the periodic table as an organizing entity. Moreover, as befits the nature of chemistry as an experimental science, the introductory (first-year) course should include experimentation and the use of scientific methodology.

Members of the panel also agree that any high school course in chemistry that is labeled as advanced study, whether or not it is structured according to an established curriculum and assessment such as AP or IB, should enable students to develop the ability to explore the chemistry concepts and laboratory practices introduced in the first-year course in greater depth and, where appropriate, to conduct some form of research. Under the guidance of a qualified advanced study instructor, desirable features of such advanced study would include some combination of the following characteristics:

• Application of basic ideas to more complex materials, systems, and phenomena

• Use of modern instrumentation, methods, and information resources

• Integration of concepts within and between subject areas, including extensions to other disciplines

• Use of appropriate mathematical and technological methods

• Extended use of inquiry-based experimentation

• Development of critical thinking skills and conceptual understanding

• Use of appropriate tools for assessing student performance and attitude that reflect current best practices

• Promotion of communication skills and teamwork

These characteristics are consistent with visions for undergraduate education articulated in the National Science Foundation’s (NSF) Shaping the Future (1996) and the National Research Council’s Transforming Undergraduate Education in Science, Mathematics, Engineering, and Technology (1999) reports. These two reports summarize what undergraduate science, mathematics, engineering, and technology (SME&T) courses, including introductory courses in chemistry, should encompass if they are to serve the dual objectives of enhancing scientific literacy and providing adequate preparation for a diverse, talented technical workforce.

Catalyzed by programs sponsored by NSF, the American Chemical Society, and other organizations concerned with improving undergraduate science education, some college and university chemistry courses are being revamped to achieve the objectives that those reports

recommend (see, e.g., ChemConnections;¹⁵Chemistry: Structure and Dynamics [Bodner, Rickard, and Spencer, 1999]; Landis and Peace [1998]; The Chemical World: Concepts and Applications, 2nd edition [Moore, Stanitski, Wood, Kotz, and Joest, 1998]; and the Discovery Chemistry curriculum developed at the College of the Holy Cross¹⁶). However, many faculty who oversee undergraduate programs in chemistry have not yet confronted and addressed these issues.

Although exceptions exist among schools and teachers, the chemistry panel finds that in general, the material taught in advanced courses (as specified in the guidebooks provided by the College Board and the IBO) fail to meet many of the criteria outlined in the previous section). In addition, the panel finds the AP and IB final examinations to be formulaic and predictable from year to year in their approaches and question formats. Thus, with sufficient practice in taking such examinations and enough drill on the major concepts that the examinations are likely to test, students can score well primarily by rote, without actually understanding the major concepts associated with the topics being tested.

The panel also agrees that laboratory should be a significant component of an advanced chemistry course, and assessment of laboratory skills should be a major part of the final examinations. However, the examinations reviewed for this study led the panel to conclude that the AP and IB final examinations do not adequately test understanding of laboratory techniques or the interpretation of laboratory data. In fact, it was only recently that the College Board added a question to the AP assessment that purportedly tests laboratory-based knowledge and skills. The panel notes that the final IB examination does emphasize laboratory-based knowledge and skills through assessments other than the final examination. For example, the IBO recommends that 25 percent of the time in the course be spent on investigations and projects, and that 24 percent of the final grade be awarded for this component. Additionally, all IB science examinations contain a required data analysis question on the second paper.

The motivation to take an AP or IB Chemistry course comes from a wide range of external as well as internal sources. Some students simply enjoy science, and such courses offer the opportunity to learn about chemistry in greater depth than is offered by a first-year course. Other students may want to take the most rigorous program of studies offered by their high school (with less regard for the specific courses taken); others may want to develop an academic profile that is sufficiently competitive to gain admission to highly selective colleges. Still others may enroll more from parental or peer pressure than from a real desire to undertake a second course in chemistry. Students and parents increasingly may see the completion of these courses as a way to enhance a student’s transcript when applying for college admission (CEEB, 1994). Parents may also believe that students in AP and IB courses have access to better teachers and more resources and that the atmosphere will be more academically focused than in other courses.

Completing an AP Chemistry course and passing the examination at the minimum level designated by individual colleges and universities may make a student eligible to earn college course credit, to place out of first-semester or first-year college chemistry, or to receive credit for completion of a general education or distribution requirement in science. Depending on the options available at the receiving institution and which option is selected, a student may be able to reduce the amount of matriculation time required for a degree, thereby saving tuition and other fees. Likewise, although the IB program was not designed to offer students opportunities for college credit, increasing numbers of colleges and universities are now offering such credit to IB students who have earned specified scores.¹⁷

The availability of a selection of AP courses, including AP Chemistry, provides opportunities for students to extend their knowledge and academic skills beyond those required by first-tier courses. Despite these advantages, however, the existence of AP courses can also create curricular difficulties. The AP program of courses can have two negative effects on the