On My Honor, by Marion Dane Bauer, 1986

Joel doesn't want to ride to the state park to climb the Starved Rock bluffs with his friend Tony -- it's too far, too dangerous, too steep. But Tony teases, Joel doesn't want to look weak, and Joel's father unexpectedly gives permission, so Joel feels he has no choice. Then Tony changes his plans and suggests a swim in the river. The danger and consequences that follow these choices place Joel in a heart-wrenching position and reluctance, anger, grief, and guilt. A short and somber realistic middle-grade cautionary tale.