TIFFIN — Almost as soon legislative changes allowed, everything but wages were shed from Clear Creek Amana Community School District teachers’ contracts.The teachers’ union agreed to the changes, the Clear Creek Amana Education Association’s chief bargainer Marcia Charbon said, primarily because of its faith in the current school board and superintendent.“I don’t have a lot of worries because I trust those people,” she said, noting little has changed for teachers’ working conditions since Iowa’s collective bargaining law went in effect.