Complex sentence: Yost hosted other educational shows prior to "Saturday Night at the Movies", most notably "Magic Shadows", another movie show, which showed classic movies in half-hour after-school episodes with introductions providing background and interesting details by Yost.
Split into simpler sentences: Yost hosted other educational shows, prior to "Saturday Night at the Movies". Most notably "Magic Shadows", another movie show, which showed classic movies, after-school, split into half-hour episodes, with introductions providing background and interesting details by Yost.