didactic

The didactic novel made every plot turn into a lesson.

The didactic novel preached at every chapter.

“The pattern prompted the city to replace didactic posters that scolded residents for impatience with screens showing expected delays and reasons for priority.”
— from the passage Waiting by Design

“She removed a didactic cartoon in which a smiling otter lectured children about greed; the estuary's history needed no mascot.”
— from the passage The Ninth Spring

“Most sharply, she dismissed their scenes of neighbors sharing food as didactic fables, arguing that art should complicate conduct rather than instruct viewers in kindness.”
— from the passage The Late Correction