Parents and students have long understood that knowledgeable, caring teachers with a wealth of teaching skills and strategies are essential to a positive school environment. The National Commission on Teaching and America's Future echoed that feeling in its 1996 report, What Matters Most: Teaching For America's Future, when it stated that "what teachers know and do is the most important influence on what students learn." The most direct way to improve the quality of mathematics and science education is therefore to improve the knowledge base of teachers, and to provide professional development opportunities which help teachers learn to facilitate student learning. According to Linda Darling-Hammond, educator and Executive Director of NCTAF, "At its root, achieving high levels of student understanding requires immensely skillful teaching -- and schools that are organized to support teachers' continuous learning."

Like other professionals, teachers have an expert knowledge base which guides their practice. Unlike other professionals, however, most teachers revise their pedagogical content knowledge -- the synthesis of their content area knowledge and general pedagogy -- in isolation. Without adequate access to the meaningful professional development programs, collegial collaboration, or feedback on their own performance, it is difficult for teachers to respond to the new mathematics and science content and theories of learning included in state and national standards.

What Matters Most explains: "If teachers are to be prepared to help their students meet the new standards being set for them, teacher preparation and professional development programs must consciously examine the expectations embodied in new curriculum frameworks and assessments and understand what they imply for teaching and for learning to teach. Then they must develop strategies that effectively help teachers learn to teach in these much more demanding ways."

According to Dennis Sparks, Executive Director of the National Staff Development Council, in A New Vision for Staff Development, a report of the National Staff Development Council and the Association for Supervision and Curriculum Development, professional development is "a means to an end rather than an end in itself; it helps educators close the gap between current practices and the practices needed to achieve the desired outcomes. This comprehensive approach to change assures that all aspects of the system -- for example, policy, assessment, curriculum, instruction, parent involvement -- are working together with staff development toward the achievement of a manageable set of student outcomes that the entire system values."

When these strategies are effective, professional development becomes very powerful. According to Teachers Take Charge of their Learning, released by the National Foundation for the Improvement of Education in 1996, "opportunities to develop professionally not only benefit the individual in shaping his or her craft, but also help ensure that best practice is everyday practice, and that the most effective approaches are used."

Most teachers are pursuing very clear goals when they seek professional development opportunities. According to the National Federation for the Improvement of Education, 73% of teachers are motivated by their interest in improving student achievement, 55% are aiming to improve their teaching skills, and 34% are seeking a broader knowledge base. Professional development programs which are connected directly to teachers' work with their students, organized around problem solving, informed by research, and sustained over time are most successful in helping teachers transform their teaching to achieve those goals. What Matters Most reports, "Over and over again, teachers attest to the usefulness of these kinds of opportunities for transforming their teaching -- and to their scarcity in most school settings."

Designing Professional Development for Teachers of Science and Mathematics suggests that effective professional development programs must address the pedagogical content knowledge of mathematics and science educators and "parallel [the characteristics of] effective learning experiences for students." The guide also identifies seven principles of effective professional development for mathematics and science educators which expand on these core beliefs: "Effective professional development experiences are driven by a clear, well-defined image of effective classroom learning and teaching; provide opportunities for teachers to build their knowledge and skills and broaden their teaching approaches; use or model with teachers the strategies teachers will use with their students; build a learning community; support teachers to serve in leadership roles; provide links to other parts of the educational system; and are continuously assessing themselves and making improvements to ensure positive impact on teacher effectiveness, student learning, leadership, and the school community."

The most compelling reason to invest in effective professional development is that it works. Successful professional development "not only makes teachers feel better about their practice, but also reaps learning gains for students, especially in the kinds of more challenging learning that new standards demand," according to Linda Darling-Hammond. Designing Professional Development for Teachers of Science and Mathematics captures this point: "Although students are not the primary clients of professional development, they are its ultimate beneficiaries. The goal of professional development is improved student learning. At the same time, student performance will not improve unless staff and organizational performance improves."

The effects of professional development are evidenced by the implementation of new teaching strategies. A recent study by the National Center for Education Statistics found that participation in professional development programs on cooperative learning, interdisciplinary problems, portfolio assessment, or technology integration led to more extensive use of those strategies in the classrooms. In short, "even no-frills staff development resulted in teachers' willingness to try new strategies to improve classroom instruction."

Trends in student achievement also support the power of professional development. Doing What Matters Most, the NCTAF follow-up to What Matters Most, found that states which made substantial investments in professional development during the 1990s have been rewarded with improved student achievement. Long-term correlation between professional development and student achievement can be seen in Minnesota, North Dakota, and Iowa, which have consistently led the nation in achievement, and which "have all had a long history of professional teacher policies, and are among the 12 states that have state professional standards boards which enacted high standards for entering teaching." In contrast, Doing What Matters Most reports that "state reform strategies during the 1980s that did not include substantial efforts to improve teaching have been much less successful."

Many important components play into the improvement of mathematics and science education, but professional development plays a unique and central role in the reform process. According to A New Vision for Staff Development, a report of the Association for Supervision and Curriculum Development, professional development is "a means to an end rather than an end in itself; it helps educators close the gap between current practices and the practices needed to achieve the desired outcomes. This comprehensive approach to change assures that all aspects of the system -- for example, policy, assessment, curriculum, instruction, parent involvement -- are working together with staff development toward the achievement of a manageable set of student outcomes that the entire system values."

What Matters Most argues simply and clearly for increased attention to professional development: "Education reform can succeed only if it is broad and comprehensive, attacking many problems simultaneously. But it cannot succeed at all if unless the conditions of teaching and teacher development change."