Teacher takes on Harsdorf

After surviving a recall attempt last summer, state Sen. Sheila Harsdorf will face another challenge this fall — again from a high school teacher. Dan Olson, Clayton, who teaches world history and government at St. Croix Falls High School, filed 709 valid nomination signatures June 1 — more than the 400 needed to get his name on the ballot for the Nov. 6 general election.