Great River School (GRS) is a Montessori charter school in Saint Paul, Minnesota, United States. It functions as a primary, junior high, and high school. Great River serves 1st through 12th grade and offers the International Baccalaureate program in its 11th and 12th grades. References External links Great River School website Charter schools in Minnesota Educational institutions established in 2004 High schools in Saint Paul, Minnesota International Baccalaureate schools in Minnesota Montessori schools in the United States Public middle schools in Minnesota Public high schools in Minnesota 2004 establishments in Minnesota