Dan Laitsch is program associate with the American Association of Colleges for Teacher Education.

All 50 states, as well as the District of Columbia, license prospective teachers. Licensure requirements vary in degree, and states may waive or lessen requirements in some situations, but they remain a key component in promoting teacher quality. To become fully licensed to teach, each state typically requires potential teachers to have a bachelor's degree, specific subject-matter knowledge, pedagogical training and clinical experience. In addition, 42 states also require teachers to pass a test or series of tests. The process plays a critical role in helping policy-makers ensure a quality teaching force and protecting the public's interest in educating our children.

The federal government defines licensure, in the words of the National Academy of Sciences, as "the process by which an agency of government grants permission to persons to engage in a given profession ... by certifying that those licensed have attained the minimal degree of competency necessary to ensure that the public health, safety, and welfare will be reasonably well protected." Using this definition, whether teachers should be licensed is not open to debate. Instead, the discussion centers around the definition of what comprises a "minimal degree of competency."

Dueling theories

What is the best way to license teachers?

Experts take two general approaches to defining the degree of competency that states should require. The first, espoused by prominent reformers such as Chester Finn of the Fordham Foundation, Dale Ballou of the University of Massachusetts and Michael Podgursky of the University of Missouri-Columbia, among others, would set the threshold for licensure at possession of a bachelor's degree and some basic subject-matter knowledge. Using the hiring and evaluation process, public-school principals, and not the state, would be the ultimate arbiter of teacher preparedness. In turn, the state would hold the principals and schools accountable for student achievement.

The second approach is supported by groups like the National Commission on Teaching and America's Future (NCTAF), the Interstate New Teacher Assessment and Support Consortium (INTASC) and the National Board for Professional Teaching Standards (NBPTS). It would require licensure based on demonstrated performance, including assessments of subject-matter knowledge, teaching knowledge and teaching skill. In addition, NCTAF has called for requirements of extended, graduate-level teacher preparation and year-long clinical experiences, as well as intensive mentoring. This view of teacher preparation envisions a continuum of experience, from initial university-based preparation through first-year mentoring and continuing professional development, ultimately leading to advanced professional certification by an independent national teaching board, the National Board for Professional Teaching Standards.

The second option is the best approach, because it would afford greater protection of the public interest in quality education. Because the goal of licensure is to protect the public interest, the level at which the standards are set depends largely on how much public protection is wanted.

In the case of protecting young children, a strong argument can be made for setting the bar much higher than it might be set for young adults. The early learning period (pre-K-3) is a critical time in a child's development. At this age social skills are established, learning habits are formed, and basic skills are obtained. Ensuring quality teachers at this age is critical, as recent research conducted by William Sanders suggests. Sanders has found that teacher effectiveness is the single largest factor affecting the academic growth of students. Sanders' research also suggests that students who experience less-effective teachers for three consecutive years have much greater difficulty catching up with their peers who have had more effective teachers. With so much riding on the effectiveness of teachers, the necessity of defining a high standard of minimal competency in the licensing of teachers becomes apparent.

Research also can help define what the characteristics of this high standard should be. Linda Darling Hammond, a Stanford University professor, recently reviewed more than 20 years of research studies examining teacher impact on student learning, and found a strong and consistently positive influence of education-course work (pedagogical study) and licensure on student achievement. The impact of pedagogical study was found to be even greater than that of subject-matter preparation. While such results may at first appear surprising, they actually make perfect sense. At some point, the extent to which a teacher is prepared in subject matter becomes irrelevant to the learner. If a student is learning how to add, for instance, a teacher's grounding in advanced calculus may be less important than a teacher's understanding of the theory and skills related to how to teach addition to a developing child. An understanding of the developmental levels, capabilities and learning styles of students is critical for teachers to determine the best approach for delivering instruction. To ensure quality of instruction, the state has a compelling interest in requiring both subject matter and pedagogical preparation.

Quality at risk

Opponents of licensure often argue that it acts as a barrier to highly skilled professionals wanting to enter teaching, and that the best way to get these professionals into the classroom is to eliminate some licensure requirements. While such a lowering of standards may allow career changers access to the classroom, care must be used in designing an alternative. Research conducted by Jianpeng Shen, a professor at Western Michigan University, indicates that alternative licensure ultimately downgrades the quality of teaching.

To maintain teacher quality, the American Association of Colleges for Teacher Education recommends that any alternative licensure programs be selective; provide teachers with the knowledge and skills essential for beginning teachers; assure teachers understand student learning styles and are familiar with a variety of instructional strategies; provide a supervised internship; and assess professional competency in the subject field and in professional studies.

A recent analysis of university-based teacher-preparation programs by the National Center for Education Information (NCEI) suggests that the concept of "traditional" preparation as being separate from "alternative" routes to licensure may be inaccurate. The study found that nearly 30% of people currently in college or university-based preparation programs leading to full licensure had already obtained their bachelor's degree, and that two-thirds of higher-education institutions nationwide have programs for candidates who enter at the post-baccalaureate level. These programs give career-changing adult learners a streamlined route into teaching, yet they continue to protect the public interest.

Qualified teachers able to meet the subject matter and developmental needs of their students, and effectively manage a classroom, are critical. The state clearly has a compelling interest -- in terms of impact on children and the need for well-educated citizens -- in establishing a high bar for teacher licensure. Lowering or eliminating licensure requirements is not only counterintuitive: It puts both the educational quality of our schools and learning opportunities for all children at risk.