Stanley finishes his hole first and heads back to camp to mull over why Zero dug his hole for him. Later, Armpit, Zigzag, X-Ray, and Squid suggest that Zero just likes digging holes. Stanley waits in the tent for Zero to return from his shower. When Zero walks in, Stanley thanks him and asks why he did it. Zero notes that Stanley didn't steal the seeds or the sneakers. Stanley is confused, but calls after Zero. He offers to try to teach him to read and Zero smiles.
"The sneakers" presumably refers to Clyde Livingston's sneakers, which makes Zero appear as though he has far more information than Stanley gave him credit for—something that aligns him with the likes of Madame Zeroni and the novel's idea of fate and destiny.
Stanley and Zero return to the tent and pull out Stanley's box of stationery. They begin with reciting the alphabet, which Zero memorizes quickly. Zero seems extremely proud. Then, Stanley prints a capital A and Zero copies it. Stanley explains the difference between capitals and lowercase letters and when to use each, which he knows Zero doesn't understand. Zero states that there are then actually 52 letters. Stanley is perplexed, especially when Zero can't explain how he did the math.
The fact that Zero is somehow a math whiz shows Stanley that he clearly didn't know Zero at all before this. In turn, this reinforces the dangers of turning someone into a one-dimensional figure rather than treating them as a living, breathing, feeling human. This in turn will begin to show Stanley that there's power to be had in kindness and in friendship.
Zero suggests that Stanley teach him ten letters per day, five capitals and five lowercase, and after five days he'll know them all. Stanley is perplexed again by how Zero did the math. Zero continues and says he'll dig part of Stanley's hole each day in exchange. Stanley agrees. He asks Zero how he figured out how many letters he'd need to do each day, but Zero again says it's just what it is. He says he's not stupid; he just doesn't like answering people's questions.
When Zero says he doesn't like answering questions, it suggests that he absolutely has more that he's hiding from both Stanley and the reader. The fact that he appears aware that this can make him look less smart brings up the possibility that Zero finds looking uneducated to be useful at times, though maddening at others.
Stanley thinks about the deal later. He knows that X-Ray won't like it, but he reasons that he still needs a break from digging to teach Zero. He thinks about the Warden's cabin and the mysterious gold tube. Suddenly, Stanley realizes it's half of a lipstick container and wonders if KB might be Kate Barlow.
Stanley's mental gymnastics here suggests that he's aware that his agreement with Zero isn't exactly fair, though he's trying to make it seem fair so that he can live with it.