Young Stewart
Shattering Glass is told from the perspective of Young Stewart, who is looking back on his time in high school five years after he graduated. He is a senior at the high school at the center of the novel and is eager to finally graduate from school and move into the next adventure in his life. Young is a follower; although he is intelligent and modestly popular, he goes along with the cruel plan to make Simon more popular and ultimately, the plan to murder Simon—all of this despite Young's privileged upbringing with parents who care for him.
Simon Glass
Simon Glass is the most important character in the novel. At the start of the novel, Simon is a nerd and a loner who has no friends. As a result of Simon's strangeness, he is picked on mercilessly by Lance, the most popular student in the school. After the arrival of Rob Haynes, Simon's life changes. Rob goes on a mission to make Simon perhaps the most popular student in school, something which shocks most of the school (especially because of Simon's meek disposition). Over time, Simon becomes more and more popular, eventually becoming the odds-on favorite to be prom king. But he is eventually killed by Rob and his group, who have abused their power and grown frustrated with the process of making Simon more popular.
Rob Haynes
After Rob Haynes arrives at the high school at the novel's center, he almost instantly becomes the most popular student. In stark contrast to Lance, who used to be the most popular student in the school, Rob is a very kind person. He has blue eyes, a big smile, and is very good-looking. However, as the novel progresses, Rob indeed is revealed: he is a violent young man who cares so little about other people that he is willing to change other people for his own entertainment. Similarly, Rob is the man ultimately responsible for Simon's murder.
Lance
Lance is the most popular student in the school at the center of the novel. Although Lance is an intelligent young man, he is a very mean and abusive person who takes personal pleasure in the despair of less-than-popular kids in his school. As the most popular student in the school, he has had free reign for quite a long time. However, once Rob arrives at the school, Lance becomes the second most famous student, which angers him. After all, Lance uses his status as the most popular student in the school to treat people around him (like Young Stewart) horribly and abusively.
