More than 122,000 teachers from all 50 states have stepped up to the challenge of achieving national board certification, a peer-reviewed process leading to recognition as an accomplished teacher.

Mike Yell, a seventh grade social studies teacher at Hudson Middle School, completed certification in 2003 and renewed his certificate in 2013. The Wisconsin educator said he would "strongly recommend national board certification to teachers wishing to take on a rigorous growth challenge that will ultimately improve their practice."

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National board certification for teachers, governed by the National Board for Professional Teaching Standards in Arlington, Va., has been gaining momentum the past 25 years. The board offers teacher certification in 16 disciplines and four developmental levels to meet the needs of almost all of America's teachers, according to the NBPTS website.

What is national board certification?

National board certification is a voluntary process that goes beyond entry-level state certification. In addition to holding a valid state teaching license, candidates for board certification must hold a bachelor's degree from an accredited institution and have three or more years of teaching experience.

National certification is not meant to replace state teaching licenses, but provides a means of promoting and rewarding accomplished teaching.

Each certificate area has a set of standards developed by teachers who are experts in that subject area and developmental level and are based on what the national board calls the Five Core Propositions. The standards provide information about what proficiencies a candidate must demonstrate to achieve certification.

Why seek certification?

Some school districts offer extra pay or stipends for teachers who earn national board certification. Others give those teachers additional opportunities for leadership or professional growth. Some districts offer no rewards and teachers seek certification for personal reasons.

Angie Jorgensen, fourth grade teacher at Pinecrest Elementary School in Hastings, said one reason she completed the process "was financial, because in Hastings, we are one of the districts that pay for national board certification."

She had also recently finished working on her master's degree, so she was in a "rigorous mindset," so moving on with national boards was "a nice transition."

Jorgensen credited a group of veteran teachers with helping her work through the process. "A few of them were closer to retirement, and they saw this opportunity to try to replace themselves as national board teachers, to get some of us younger teachers certified before they left. They were a huge support."

Collaboration with other teachers is an important part of the national board certification process and Mike Fuller, band teacher at Meyer Middle School in River Falls, said that "the more I learned about the process involved, the more interested I became in it. I learned of three other area music teachers who were considering working on their national boards and the opportunity to have a built-in network and support system helped me decide to go for it."

Other teachers are motivated by personal growth.

"I am a lifelong learner," said Betsy Weis, math teacher at Farmington High School, "and I wanted to step up to a new challenge, especially since I knew it would improve my teaching skills."

What do teachers need to do?

Teachers have to use the standards for their certificate area to guide responses to four components which require candidates to demonstrate content knowledge and instructional methods. Candidates must write extensive essays explaining lessons in their classrooms, analyzing their lessons, and reflecting on how to improve the lessons. They also provide videos of themselves teaching in their classrooms and take a computer-based test on their subjects.

"The NBC questions are intense and require one to reflect on student data, teaching practice, leadership, collaboration, community involvement, and technology use," Weiss said. "I discovered new and better ways to improve student learning."

The process can take as little as one year to complete, but many teachers choose to spread it out over three years. The challenging nature of the assessments means that many candidates must repeat parts of the process as part of the learning and growth supported by the national board.

"It was very time consuming," said Mary Rumpel, math department head at Ellsworth High School in Pierce County, Wis. "The challenging part was that you had to explain why you teach in the way that you do. For example, in one section, you had to take a couple of students and the assignments you give them, and explain how you get these dynamically different students to each learn the subject area, documenting what you've explained."

She added, "It is a big project, one that will take a lot of self-reflection, a lot of trials and errors, and a lot of weekends to do well."

This process also requires a financial commitment. The full process costs $1,900, and many candidates are able to find help with this from grants, loans, or school district funds. Others pay the fee themselves.

How does certification affect student learning?

"More than a decade of research from across the country confirms that students taught by board-certified teachers learn more than students taught by other teachers," wrote the national board on its website. They include links to several academic studies about the effects of national board certification on students.

"The national boards process involved looking at what I was already doing in the classroom and explaining its impact on student learning," Fuller said. That required me to think a lot about my teaching strategies and consider how effective they were in helping students to grow. The four papers that candidates are required to write make you articulate why you do what you do and how it positively impacts students."

Previously named National Social Studies Teacher of the Year, Yell said the "most important impact of board certification was internalizing the process of researching and staying on top of the scholarship in education as well as in my content area, and in the continuing process of reflecting on everything I do in the classroom."

Achieving national board certification was not an end for Rumpel, but a beginning.

"I believe by holding the certification, I feel like I cannot let the students down," she said. "I have to keep challenging myself each year and figure out how to keep getting better."

When Tim Collins, superintendent of Hastings Public Schools,interviews new teachers, he said he is looking for "a strong work ethic and the desire to grow professionally for a lifetime. Teachers who decide to go through the National Board Certification process exemplify those two characteristics."

Those teachers often provide a positive role model for other teachers in their buildings and districts.

"When a person grows professionally they bring that level of confidence and best practices to their colleagues both directly and indirectly," Collins said. "The process of National Board Certification helps a teacher to become better informed in their practice, reflective in the classroom, and overall strengthen their personal teaching strategies."