Education Minnesota scored a rare win in the charter-school sector Tuesday night when 25 teachers at a German immersion school in St. Paul gave 80 percent support to forming a union, making it the sole unionized charter school in the state.

Charter schools have been an elusive target for the statewide teacher organization, despite its almost total success in organizing district teachers across the state.

Only four charter-school teaching staffs have been union-represented since the first such school opened in 1992, but none has been recently until the vote at Twin Cities German Immersion School. The next step will be contract bargaining.

The win may represent something of an anomaly. A substantial portion of the teaching staff is made up of German-born educators who enjoyed better working conditions in their home country, according to teachers who helped the organizing drive.

The K-8 school, which is in its ninth year, enrolls 375 students. Chair Matt Schneider said in a statement that the school's board "supports our teachers' rights, including their right to form a union." He said the school's growth and high scores on both Minnesota and German assessment tests shows that teachers are skilled and dedicated.

A number of factors have weighed against broader organizing of Minnesota charter schools. Many have high staff turnover, which makes sustaining an organizing drive difficult. And until 2009, teachers also were required to make up a majority of a charter's board, making them both management and labor.

"There can be a little bit of a fear factor … the freedom to speak may not be as prevalent," said Denise Specht, Education Minnesota's president. But she praised the immersion school's teachers, saying they are devoted to improving working conditions at a school to which many of them send their own children.

More common in Wisconsin

According to the National Alliance for Public Charter Schools, 12.3 percent of the nation's charter schools had collective bargaining agreements in 2009-10. Wisconsin had the highest number at 121, and five states, including Iowa, required charter schools to have union staffs. Minnesota leaves that choice to teachers.

Minnesota's first charter school, City Academy in St. Paul, was union-represented initially, but no longer is due to a reorganization. Charter schools near Hibbing and Forest Lake that unionized later closed. Teachers at Ubah Academy in Hopkins began the organizing process in 2010, but by the time they won a protracted court fight over who was eligible to vote, turnover in staff had made moot the win.

According to a just-released study by a labor economist and an education professor, data suggest that teacher unionization doesn't significantly help or hurt student achievement. They studied student achievement trends at 1,126 California charter schools. some of which were always unionized, some of which chose to unionize, but most of which were nonunion.

The only impact they noticed on achievement came during the year in which workers unionized. According to co-author Aaron J. Sojourner at the University of Minnesota, that dip may have reflected the union issue distracting both teachers and administrators, but he said that student performance rebounded relatively soon.

Two teachers involved in the organizing drive said that due-process issues are part of their quest to form a union at a school at which they have at-will contracts with less job security. "It's just part of the German employment practices to have a contract," said one teacher, Katie Stephens.

European standards

"We wanted the same things that other public schoolteachers have around here," said another teacher, Susan Johnson.

According to state Department of Education data, teachers at the school were paid an average salary of $38,822 in 2013, compared with a statewide average of $54,945. That comparison doesn't account for possible experience differences.

Johnson said that a majority of the school's staff is German-born. Some have taken leaves to teach here for three years on a visa, while others are permanent U.S. residents. Specht said the German-born teachers have remarked that they're paid much less here than in Germany.

Steve Brandt • 612-673-4438 Twitter: @brandtstrib