Jade Dragon
Jade Dragon herself is a symbol. She is an innocent nine-year-old Chinese girl with an incredible gift for mathematics and scientific disciplines, and she merely published some research before being taken captive and orphaned by Dr. Hatch and the Elgen. She comes to represent the world's goodness and its abilities; the Electroclan must retrieve her before Dr. Hatch exploits her abilities to further his own power, just as he tries to do with everything good. The codename "Jade Dragon" is evocative of this symbolism; she is a human, but more importantly for the overarching plot, she is a symbol of what Michael and the Electroclan are protecting.
Nichelle
Nichelle is almost the opposite of Jade Dragon in the nature of her symbolism. While Jade Dragon is good and innocent, her "powers" being positive contributions to society, Nichelle is bitter and resentful, and her power is essentially negative: it takes away the power of others. In the first novel, she was a major obstacle for Michael to defeat. She reluctantly joins their team in this fourth novel, however, and by the end, she is growing to become a better person, as evident in her changed expression when Michael includes her in the group ("She looked at me with a peculiar expression, then I saw a look I hadn't seen on her before. She put her hand down. 'No. We're not like them.'" - Ch. 37). She represents the evil the Electroclan is impacting and redeeming, the opposite force to Hatch's corrupting influence.
Bullets
In the course of this novel, Gervaso teaches Michael how to deflect bullets by pulsing and creating an electric field. From that point on, bullets represent the dangers of the world that no longer pose a threat to Michael as he grows and matures. This elevation beyond the base and physical emphasizes the novel's transition from a material struggle to a philosophical one.
Michael's Tourette's
Michael's Tourette's Syndrome is a symbol of his imperfections. It would be easy to make Michael seem like a generic super-powered kid, especially since his power is stronger than that of everyone else. His condition, however, proves that he's not superhuman; he's a relatable character who's fallible. These electric teenagers might be more than simply human, but they're so similar to the target audience of this novel that it would inspire them to be great as well.
Gervaso's Medal
Before the departure, Gervaso gave Michael his Distinguished Service Cross (the US's second-highest military award; he earned it during Operation Desert Storm). The transferring of this medal symbolizes the Resistance placing all their hope on Michael, as he's going to do what they are unable to. It's a huge honor for Michael, but also a huge burden, and many times he doesn't feel deserving; by the end, though, he fulfills his mission and proves himself worthy.
