• actively participate in the ongoing planning and development of the school science program.

Similarly, the NCTM’s Professional Standards for Teaching Mathematics (1991)⁴ envision teachers as decision-makers who must bring to their classrooms the following:

• A deep content knowledge and understanding of mathematics beyond the mathematics they are teaching.

• An understanding of students as learners and their previous and current knowledge about the subject area.

• Carefully selected learning goals.

• Knowledge of a variety of pedagogical strategies, including the use of modeling and simulation.

• Experience knowing how to frame questions, choose activities to address misunderstandings they know students have, and assess student learning appropriately.

According to the new Principles and Standards for School Mathematics, effective mathematics teachers use strategies and approaches that range from extended student explorations in small groups to direct teaching. As student needs change, teachers make deliberate shifts among these strategies. Teaching mathematics well “takes deep insight about mathematics, about teaching, and about learners, coupled with a sound and robust mathematics curriculum and thoughtful reflection and planning” (NCTM, 2000).

Linked with these standards for teaching is changing expectations about what should receive greater emphasis in science and mathematics instruction. Table 1-1 is an example from the National Science Education Standards that illustrates these differences.

Both the science and mathematics standards call for teachers to ensure that all students have learning opportunities in science and mathematics that result in measurable learning outcomes (NRC, 1996a; NCTM, 2000). However, today’s K-12 student population in the United States is much more diverse, in terms of different languages, cultures, and ethnicities, for example, than it was just a few decades ago, and teaching standards-based science and mathematics to this new generation of students can pose great educational challenges for teachers.

Expectations for increased performance by K-12 students have shifted dramatically during the past 10 years with the development and publication of standards and curriculum frameworks of individual states, many of which are