After arrogant and spoiled Harvey Cheyne is taken in by a group of fisherman, he has to acclimate to life on the sea and grow in resilience and perseverance. The novel builds to a peak with Cheyne's tribulations in trying to prove himself and become an integral part of the fishing crew.

The climax of the novel occurs when the We're Here is racing to fill up its hold with fish and Cheyne is in charge of filling it. He works tirelessly and diligently, and they eventually fill up their hold faster than anyone around them, showing Cheyne's growth and his newfound success in sea life. His journey ends when they come to port in Boston and he reunites with his parents—proud of his accomplishments and confident in his abilities as he plans to head to university at Stanford.

In Captains Courageous, Harvey Cheyne is trying to prove that he is a good fisherman and that he can hold his own when it comes to being a member of the fishing crew. To that end, he is racing to fill up the boat We're Here with fish in order to prove that he can fill the hold the fastest and show everyone that he can, in fact, succeed as a fisherman/sailor.

Up until that point, he was clearly a spoiled and wealthy child with little to no successes of his own. So, at the climax of the story, he is attempting to succeed in this relatively small thing to prove that he is capable. When he does win, he heads back to port with pride.

The climax of Captains Courageous is when the boat Harvey is on wins the contest by filling its hold with fish before the other boats can do so.

Though Harvey has many experiences with the crew of the We're Here, the last and most important one takes place in early September. They've almost reached land so that Harvey can get in touch with his parents, let them know he's alive, and go home. First, though, they're going to participate in an annual contest to see which ship can fill its hold with cod and halibut the quickest.

This is the climax because Harvey is shown to be a different person at the end of his voyage than he was at the beginning. He's helpful, controlled, and kind. At the beginning, he was demanding, selfish, and petulant. Now he's the kind of person his parents can be proud of. When they win the contest, the change in Harvey is confirmed. All the work the sailors and Harvey himself did has resulted in a change in his character.

The climax to this story comes when the We're Here wins the race to fill its hold with fish out at the submerged rock.  It then heads back to port where Harvey Cheyne will return to his previous life.  It is at this point in the story that the main conflict is over.

The main conflict in the story was that of Harvey against himself.  He had to learn how to be more than the spoiled rich child that he had been.  This was accomplished over the course of the fishing boat's voyage.  When the We're Here fills its holds first, it is a symbol of sorts -- it shows us conclusively that Harvey has become a man.  He has proved himself as a valuable member of a fishing crew.

After the boat wins the contest, we get into the falling action of the story where we start to see what the consequences of Harvey's change will be.  The part of the book where the We're Here wins the contest, then, comes between the rising action and the falling action.  This means it must be the climax of the book.