Robert E. Howard's school assignment What I did in vacation recounts his adventurous summer vacation spent with friends. The narrative begins with Howard expressing his joy at the onset of a four-month vacation from school. He details a month of leisure activities such as fishing, swimming, hunting, and exploring, followed by a thrilling hunting expedition with his friends in the Rocky Mountains.

The group's journey is marked by excitement and danger, starting with an encounter on the Ute reservation where inebriated braves chased their car while shooting wildly, narrowly missing them but hitting the car and Bill McGarthy's hat. Their adventures continue with a humorous incident involving a mistaken rattlesnake alert that turned out to be a horned toad, causing a comical overreaction from the group.

The real adventure begins when they reach the mountains, where every member faces various challenges: Wilk McLane stirs a hornets' nest and is forced to dive into a stream to avoid being stung, Jimmy Reagan is chased by a grizzly bear which the group eventually kills, and Bill McGarthy spends two hours treed by a moose. Howard himself experiences a close call when he falls over a precipice and is saved by hanging onto a ledge until rescued by their guide.

The vacation ends with a visit to Salt Lake City and a leisurely return home just before the new school term. Throughout the narrative, Howard vividly portrays his deep connection with nature and his enjoyment of the freedom and excitement that the wild provides.