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How important is teacher experience?

Most successful schools have a healthy combination of experienced teachers and new teachers. The experienced teachers give the schools stability and serve as mentors to the new teachers. The new teachers bring fresh ideas and enthusiasm. Experience is certainly important but interestingly enough some studies have shown that the benefits of experience become evident after just a few years of teaching and seem to peak at four or five years. In other words, teachers don't necessarily become more effective the longer they remain in the classroom.

What does a teacher's education level tell you about his qualifications?

Teachers who have advanced degrees have shown a commitment to advancing their own learning, and are generally paid more for having an advanced degree. Some studies have shown that a teacher having an advanced degree does not have any significant effect on student achievement gains at the elementary level, but having an advanced degree does have an effect at the high school level, particularly in advanced courses in math and science.

What does it mean if a teacher is fully certified? What if the teacher has an emergency credential?

To be fully certified, it generally means that a teacher must have graduated from an accredited college, completed an approved teacher credential program and passed a test of their academic skills. It's important to note that each state may set its own requirements for teacher certification. In New York, for example, in order to obtain permanent certification, every teacher hired must have a master's degree or complete one within seven years of being hired.

Teachers who are not certified can earn an emergency credential if they have graduated from college and pass a state test. Generally school districts hire emergency-credentialed teachers to fill posts when they cannot find fully certified teachers. These emergency-credentialed teachers may have bachelor's degrees and/or professional experience in the subjects they teach, but lack the required teacher training and experience. A high percentage of teachers with emergency teaching certificates may indicate that the school has difficulty attracting and retaining qualified teachers.

Some states have created alternate routes to certification in order to meet the requirements of the No Child Left Behind law to employ highly qualified teachers. These alternate routes to certification, which may vary from one state to another, are particularly useful for subjects such as math and science, where it is becoming increasingly difficult to find credentialed teachers. Teachers who have prior experience in these fields may find an easier, faster way to get certified through alternative certification.

How important is certification?

Teachers who have completed a teacher preparation program may gain valuable knowledge in their curriculum area and classroom management skills, but this does not necessarily guarantee higher levels of student achievement. Some programs, such as Teach for America and New York City Teaching Fellows, provide alternate routes to certification, and have produced teachers who raise achievement levels for students. Another factor — the level and quality of support teachers receive once they are in the classroom — may be as important as the type of credential they have in ensuring their students' success.

What does the No Child Left Behind law (NCLB) say about teachers?

According to NCLB, teachers must be "highly qualified." To teach elementary school, they need a bachelor's degree and must pass a rigorous test in core curriculum areas. To teach middle or high school, they must be certified in the subjects they teach by passing a test, or by completing an academic major, teaching credential program or comparable coursework.

The law has caused administrators to focus more on recruiting efforts, particularly for hard-to-staff schools, and to focus on assigning teachers to classes in their areas of expertise.

However, the law has also had some unintended consequences for some experienced teachers without the proper credentials. For example, Jefferds Huyck, a Latin teacher with a doctorate in classics from Harvard University and a teacher for 22 years in high school and college, is not considered "highly qualified" under NCLB because he doesn't have a teaching credential. Along with two other teachers with doctorates at Pacific Collegiate Charter School in California, he decided to leave the school rather than spend two years and $15,000 on a teacher credential program geared to beginners.

No state met the 2006 deadline to have a highly qualified teacher in every classroom. The U.S. Department of Education extended the deadline until June 2007 and ordered states to explain how they would meet it or risk losing federal funds. In July 2007, Margaret Spellings, the U.S. secretary of education, sent a letter to all the chief state school officers informing them that no state would lose federal funds solely because they had not reached the goal of 100 percent highly qualified teachers and so long as they could show they were making efforts to meet the goal. Hiring and retaining enough highly qualified teachers, particularly for low-performing schools where the need is the greatest, has been a challenge for many school districts. And without qualified teachers, it is no surprise that it is difficult for schools to close achievement gaps.

What other factors should you consider when evaluating the quality of teachers at your child's school?

There are some qualities that can't easily be measured but are certainly important in a teacher: a caring attitude, ability to relate to students, organizational skills, enthusiasm and love of learning. Teachers are also influenced by relevant staff development and training, mentoring opportunities and school-wide goal-setting. New teachers benefit from one-on-one mentoring while all teachers can benefit from meeting in subject and grade-level teams with other staff, and having the opportunity to reflect on and analyze their teaching practices.

Questions Parents Should Ask

You can be on the lookout for all these qualities in action when you visit your child's school. Here are some questions you might ask your principal about teachers at your school:

• Do teachers receive additional training once they are on the job? What is that training?
• Do new teachers have a mentor at the school or within the district?
• Do teachers meet frequently in grade-level and subject teams?
• Do teachers use state test scores to assess the needs of their students?