 Landsberger attended Mounds View High School (Arden Hills, Minnesota) where he graduated in 1973 after leading the Mustangs to the 1972 AA State Championship as a junior.In his senior campaign, he averaged 26.1 points per game, and led the Mustangs back to the state tournament and the consolation championship.Over his high school varsity career, he scored 1,290 points and grabbed 910 rebounds.