I just returned from ten days in Alaska where I saw the word "charter" on hundreds of signs throughout the state. Sure, the word was on signs for charter fishing boats, but the state also has 26 charter schools in operation. Alaska's charter school law is weak, receiving a "D" rating from the Center for Education Reform.
Alaska's charter school law passed in 1995 and permits up to sixty charter schools. Some of the provisions that make the law weak are less autonomy than other states (i.e. an "academic policy committee" instead of a governing board) and the charter school is bound by the authorizing school district's collective bargaining agreement with teachers.
Several of Alaska's charter schools focus on the Alaska Native heritage and culture. The Ayaprun Elitnaurvik Charter School in Bethel uses the immersion method of teaching Yup'ik to elementary school-aged students. In fact, note this list of spelling words for 2nd and 3rd grade students. Other charter schools use Spanish immersion, the Spalding method and a handful are homeschool programs.
Many of the state's charter schools are only accessible by plane, boat or dog sled since there isn't a road system in rural Alaska. About eight rural charter schools operate in Colorado, but at least they have a road to the school!