A Discipline-Based Approach to High School Science

(From the Ohio Department of Education draft, April 2007)

Model Overview

The discipline-based model addresses grades 9, 10, 11, and 12 benchmarks and grade-level indicators of the Ohio Academic Content Standards, K-12 Science. Semester-long courses are offered throughout high school in addition to year-long courses, with the option to begin coursework in the 8th grade. Students may earn up to a full unit of credit in life sciences and physical sciences, and one-half unit of credit in Earth and space sciences by the end of grade 10. Coursework, instruction and assessments are organized in a way that allows students to build on previously learned science knowledge and skills. All courses are laboratory courses that provide opportunities for authentic student inquiry into the discipline and encourage extension of content knowledge to real-world applications and technological design scenarios.

Science teachers may be assigned to teach courses for which the teachers have deep knowledge of the science discipline area(s). This model helps provide students enriched opportunities to learn science through instructional units designed by teachers who have deep understanding of the content and content-specific science processes (Before It’s Too Late, A Report to the National Commission on Mathematics and Science Teaching for the 21st Century, 2000).

Model Rationale

The discipline-based model prepares students for success on the Ohio Graduation Test (OGT) in science, ensures that they meet state graduation requirements, and equips them to enter a variety of career paths or additional post-secondary studies. Prior to the OGT, courses in this model incorporate all three science content standards areas, Life Sciences, Earth and Space Sciences and Physical Sciences. Additionally, benchmarks from the Scientific Ways of Knowing, Scientific Inquiry, and Science and Technology standards are embedded throughout the courses in this model. Incorporating science processes into science content is necessary for students to have a deeper understanding of science and to develop an appreciation for the connections across scientific disciplines (Krueger and Sutton, 2001; National Research Council, 1995). Through the use of inquiry-based learning and real-world applications, students gain an understanding of the nature of scientific processes and scientific ways of knowing as well as the way in which science is relevant to their daily lives (Krueger and Sutton, 2001).

The successful implementation of the Ohio Academic Content Standards, K-12 Science requires a comprehensive science program that includes coursework in physics, chemistry, biology, and Earth and space sciences. This model suggests a curriculum focused on discipline-based instructional cycles is an effective approach for many students (Northwest Regional Educational Laboratory, 1999). Focused instruction in this model includes a scaffolding of concepts that allows students to build upon prior knowledge (Krueger and Sutton, 2001).

Course topic sequencing is an important component of this model. Content should be sequenced in a way that allows students to build on prior knowledge as well as accumulate required credit in the major discipline areas. Furthermore, a five semester course sequence beginning with physical sciences and culminating with a life sciences or an Earth and space sciences course provides a pathway for students to transition from concrete to abstract thinking. Research suggests that an early introduction to foundational physics concepts may improve student achievement in all sciences (Aldridge, 1997; Schmidt, et al., 2001; Yager and Weld, 1999). Scaffolding of essential science concepts can be reinforced and supported by incorporating these concepts in subsequent learning cycles.

This model offers additional benefits for students and schools. A mix of semester and year-long courses provides greater flexibility in course selection, thereby, meeting the needs of a variety of students. Students are encouraged to take control of their own learning through the selection of courses that meet their individual needs and interests. Encouraging students to take control of their learning experience supports an effective learning process (National Research Council, 2000). Students who are interested in science may choose to take more than one course each semester allowing them to schedule more advanced science courses sooner in their high school experience. Students can also select courses (beyond those required by the school and the State) to focus on a defined discipline and pursue more in-depth content knowledge in a discipline of high interest or applicability to future goals or career plans. Semester-long courses may be more suitable to addressing standards by focusing on fewer fundamental science concepts in greater depth rather than covering many topics in a year-long course (Krueger and Sutton, 2001).

Schools may find this model advantageous for a variety of reasons. Teaching assignments can be made so that teachers can teach to their strengths and area(s) of licensure/certification. A greater variety of courses can be offered to a larger number of students. The discipline-based titles of this standards-based model help students, parents, teachers and administrators easily recognize and communicate the course content. This model prepares students for non-remedial college-level science coursework and promotes interest in a wide variety of science careers. Semester-long courses also can facilitate the efficient management of resources such as laboratory space, laboratory equipment and supplies, as well as textbooks and other instructional materials. Because many textbooks are written for discipline-based courses such as chemistry, biology, or Earth and space sciences, a school district can choose a single textbook and designate which topics, chapters or units are taught in which course.

Model Description

The discipline-based model presents a comprehensive discipline-based approach to implementing the Ohio Academic Content Standards, K-12 Science. Students completing this model will have the content equivalent of one year of life science and a minimum of one semester each of physics, chemistry and Earth and space sciences by the end of grade 10. The introductory discipline-based courses in this model offered in a semester-long format include Introduction to Physics, Introduction to Chemistry and Introduction to Earth and Space Sciences. The science content for the Physical Sciences standard at grade 9 is divided between the Introduction to Physics and Introduction to Chemistry courses, providing more time to develop foundational physical sciences concepts. The content in the Life Sciences standard for grade 10 is presented in a year-long course, Introduction to Life Sciences, that builds student understanding from concrete and observable concepts, to more abstract and applied life sciences concepts. The content of the Introduction to Earth and Space Sciences course is drawn from the Earth and Space Sciences standard indicators for both grade 9 and grade 10.

Following the semester-long introductory courses, students can enroll in year-long courses in each discipline (chemistry, physics, advanced biology, and Earth and space sciences) which provide greater depth of content knowledge extending beyond that identified by the 11th and 12th grade standard benchmarks and indicators for Physical Sciences, Life Sciences and Earth and Space Sciences. Students are also offered the option of completing more semester-long courses in Environmental Sciences and/or Physical Geology that build on the foundations provided by the introductory courses.

Students are prepared by the introductory course in each discipline to transition to a year-long discipline-specific course. The combination of the introductory course with a year-long course would provide appropriate preparation for enrollment in an Advanced Placement course or for rigorous post-secondary work leading to a science-intensive career. While in this model, students could take Advanced Placement or International Baccalaureate courses after the completion of the introductory course in a specific science, they may experience gaps in content knowledge. The transition to an Advanced Placement course would be improved by enrollment in the introductory course followed by the completion of a year-long course in the specific discipline. AP and IB courses, when offered by the school, are in year-long formats due to the prescribed curriculum of each program. Schools can develop other elective science courses, as needed, to meet student needs.

Courses for the Discipline-Based Model

Each discipline-based model course allows students to meet the K-12 Science benchmarks in the relevant discipline area. Courses address discipline-specific, standards-based content knowledge. This content is integrated into the teaching of reasoning and process skills included in standards for technological design, scientific inquiry, and scientific ways of knowing, and reinforce connections within and across the scientific disciplines. For example, in the Introduction to Earth and Space Sciences course, students study the development of scientific theories connecting plate tectonics and the formation of Earth. The Environmental Sciences course includes an investigation into the capacity of technology to address climate change; and the Introduction to Life Sciences course connects mathematical analysis with biological sciences in the study of population growth and carrying capacity. In each course, topics are presented in the context of historical developments and current perspectives in that discipline. Students gain an understanding of the nature of scientific inquiry by engaging actively in authentic inquiry and discussions of the development of theory and discipline-specific scientific knowledge.

Course sequencing requires that all four introductory level courses be completed by the end of the 10 th grade year so that students are prepared for the OGT. One (or more) of the semester-long introductory courses can be offered in the 8th grade (preferably during the second semester), providing students the opportunity to begin the sequence early. If this 8th grade option is not utilized, students will need to take two science courses during one semester of either grade 9 or grade 10 in order to ensure completion of all four courses prior to the end of grade 10 and appropriate preparation for the OGT. The preferred course sequence for this model would commence in the 8th grade with students taking Introduction to Physics followed by Introduction to Chemistry and Introduction to Earth and Space Sciences in the 9th grade. These courses lay the foundation for scaffolding essential physical and Earth sciences concepts into the Introduction to Life Sciences course taken during the 10th grade year.