This document introduces several individuals including Carl, a 13-year-old student whose parents are a teacher and nurse. It also describes Peter, Carl's 15-year-old best friend who is also a student. The document next discusses Michael and Joseph, 16-year-old twin brothers who are students, with different hair and strengths in maths and physics. Finally, it briefly mentions another boy whose parents are lawyers with a big house and garden in the city center.