Numbers are a motif that appears throughout the narrative to demonstrate Charlie’s genius and highlight the value of her STEM education in surviving dangerous situations. Charlie’s first appearance in Chapter 1 includes a demonstration of her ability to visualize numbers and equations in her head, such as when she uses the numbers to not only survive the ski jump from Deadman’s Drop but also make it “look awesome.” This ability allows her to visualize the physics of the ski jump—the angles, her speed, and so forth. She can also visualize numbers to work out probability and statistical models.

Charlie did not need to learn this skill, as it happens naturally: “Even when she was a little kid, well before anyone had tried to teach her math, the numbers had come to her” (30). This is one of the skills used to establish Charlie’s genius. Her genius and her STEM education, as demonstrated through her ability to visualize the numbers, prove paramount to her survival throughout the story. She uses the numbers while skateboarding to chase and tackle Marko and retrieve the Sherlock Holmes book. Importantly, she also uses the skills she demonstrated in the second chapter to escape the fire at the observatory in the final chapter.