Wisconsin is part of a national effort to improve how teachers teach. This year, 80 school teachers became nationally board certified.

Jennifer Martens had been teaching for 20 years in the Plymouth School District when she got national board certification in 2008. She already had a master degree, but said she "needed the challenge" and wanted to keep up with changes in education, "I learned a lot about my teaching and I learned a lot about things I had been doing for years that were still really, really good; some things that I had stopped doing that I needed to start doing again."

For instance, Martens resumed more "hands-on" learning in the classroom. Nationally, only 2.5 percent of teachers in America are nationally certified. Michelle Accardi is with the National Board for Professional Teaching Standards. She notes that a Harvard study finds higher student achievement among students taught by certified instructors, "Those learning gains adds up for our students; in particular for our students who may be impacted by poverty or other things where we're trying to maximize their academic potential and their high school graduation rates."

Accardi says the greatest impact can be in science and math, areas the U.S. has been trying to emphasize, "I'll be very honest with you. On a personal level. I agonize for the children who don't have a [national] board certified teacher and think about how much progress we could be making if they had a board certified teacher."

Two thirds of states, including Wisconsin, provide salary incentives. The states also provide stipends to partially cover the cost of obtaining what many consider the highest professional achievement in teaching.