Alex, age 14.

From his family, Alex inherits a love of the outdoors. He enjoys camping with his family, hiking in the mountains, swimming in mountain lakes, and bicycling. Alex also has some skill with amateur photography. He enjoys going to the movies with Andrew (when he’s not babysitting Courtney) and Amy.

Ali, age 13.

A friend of Harry and Tim’s who shares some of their interest in fantasy and magic, Ali is more grounded in the real world than the twins. He enjoys skateboarding, doing science experiments, and going to the mall to see movies and to eat. He’s a good friend of Rachel, who frequently joins him in his sojourns to the mall.

Alia, age 13.

Alia plans to become a scientist when she grows up. She enjoys designing and conducting physics experiments, and she is equally enthusiastic about chemistry. Not surprisingly, science class is her favorite class. Alia plays an ongoing astronomy challenge game with her friend Kim.

Amy, age 14.

Amy enjoys swimming and diving, and is the best all-round diver at her school. She has won city and county diving championships for her age group. For recreation, Amy likes to scuba-dive in the ocean. Amy is a friend of Andrew, who is her science partner, and of Alex, with whom she sometimes goes hiking or swimming.

Andrew, age 14, and his niece Courtney, age 6.

Andrew is frequently stuck with babysitting his niece Courtney, both of whose parents (Andrew’s older brother and his wife) work full-time. Despite his grumbling, he’s fond of Courtney and constantly keeps a close eye on her. Two of his closer friends are Amy and Alex. Courtney is a fun-loving girl who enjoys being pulled around in a red wagon by Andrew and playing with her toys.

Antonio, age 14.

Antonio is an avid inline roller-skater who unfortunately gets easily distracted when he skates. Fortunately, he always wears a helmet, something he decided to do after colliding a couple times with skateboarder Ali. Antonio is an avid cook. He specializes in Italian dishes like pizza and spaghetti, which he also loves eating—sometimes to excess. His friend Mario often samples Antonio’s gourmet dishes.

Erica, age 13.

Erica enjoys playing tennis and engaging in other sports. Her bedroom features an aquarium, where she keeps several goldfish. She likes to study their behavior in preparation for being a zoologist one day. Easily chilled on winter nights, Erica keeps a space heater in her bedroom to keep her warm before she goes to bed (she turns it off before turning off the lights).

Hugh, age 13.

Hugh is the class clown—literally. Hugh wants to be a clown when he grows up, and he has already begun working toward that goal by working as a clown at a number of birthday parties. Hugh particularly enjoys science when he can apply what he learns to everyday life. Hugh also enjoys listening to his favorite rock groups on his personal CD player.

Harry and Tim, age 13.

Identical twins Harry and Tim are fans of fantasy fiction, comic books and films, and enjoy doing magic tricks and shows. Their favorite fantasy series are about their British namesakes: The Harry Potter™ novels and films, and The Books of Magic™ comics (about teenage magician Tim Hunter). The twins tend to find magic in everyday life. The boys dream about becoming astronauts and visiting other planets. They are good friends of Ali and Rachel.

Jocelyn, age 13, and brother Kenny, age 9.

With her parents working full-time, Jocelyn has to spend a great deal of time with her little brother Kenny. Though she grumbles to her friends, she gets along pretty well with her brother, particularly since they have a good working arrangement: If he does the chores (like mopping the kitchen floor and doing the laundry), she’ll take him out sailing, which they both love. Kenny also enjoys playing with his yo-yo and his fire truck.

Jorge, age 13.

Jorge’s first love is baseball, and he’s good at it. Jorge frequently plays in pick-up games down at the park, and sometimes plays in games that are more organized. Jorge is a particularly good batter, and he has hit a few home runs. Jorge usually plays ball with his close friends Sofia and Orlando. Jorge is also a budding auto mechanic who helps keep Sofia’s car running.

José, age 12.

José hopes to become an engineer when he grows up, and has an abiding interest in all things electrical. He enjoys building electric circuits and experimenting with electricity. He also enjoys winter sports like sledding and sleeping until noon on weekends. José has had a reputation as the class brain since he skipped second grade, but he doesn’t always have the right answer. José is a good friend of Raja, a frequent study partner.

Kerri, age 14.

Of all the topics in her science class, Kerri likes chemistry the most. She has aided and abetted her friend Rajiv in his controversial chemistry experiments, and they are frequent study partners. On cold winter nights, Kerri enjoys a cup of hot chocolate or tea. Kerri also enjoys playing softball.

Kim, age 14.

Kim loves all things astronomical. Not only is she a vast store of information concerning planets and stars, she enjoys discussing astronomy with her friends and catching up on the latest research on planets and stars. Kim is also an avid user of the Internet. Kim plays an ongoing astronomy challenge game with her friend Alia.

Luisa , age 14.

Luisa frequently plays soccer with her friends Maya and Michelle. She’s the best player of the three friends, and one of the team’s stars. Her goal gave her team the county championship, even though another attempted goal deflated the soccer ball. Luisa often helps Maya shop for and cook her gourmet dishes.

Mario, age 13.

Mario is on the school’s hockey team, and is one of their better players, if not quite the school star. After a grueling hockey game, Mario enjoys the refreshing taste of chilled apple juice. Mario is a friend of Antonio, and a frequent test subject of his cooking experiments.

Maya, age 13.

Maya enjoys playing soccer with her friends Michelle and Luisa. Not the best of players, Maya plays more because she loves the social atmosphere than because she loves the game. Maya’s first love is cooking, and she has a number of delicious specialties. She is a bit accident-prone in the kitchen, where she has burned her hand a few times.

Melissa, age 14.

Melissa has a strong interest in archery and dreams of becoming an Olympic contestant. With constant practice and a keen eye, she has become an excellent archer. Her sharp eye has also helped her accuracy with slingshots and darts. Melissa uses the skills she learned in science to help her with her archery—for example, conducting experiments to determine how bow strength depends on various factors.

Michelle, age 13.

Michelle frequently plays soccer with her friends Luisa and Maya. She’s a good player, but not the star of the team. Michelle is more concerned than her friends are with her looks, spending quite a bit of time in front of the mirror with her steel comb. She enjoys science, particularly chemistry.

Orlando, age 14.

Orlando enjoys baseball almost as much as his friend Jorge and cousin Sofia. He’s a better fielder than he is a batter. Because he is so familiar with Jorge’s batting style, he’s frequently picked for the opposing team so that he can catch Jorge’s fly balls. Orlando has a laid-back personality that makes him popular at school. Orlando’s mother Maxine is an architect.

Rachel, age 13.

Rachel is a good friend of Ali, with whom she frequently makes trips to the mall to eat lunch at fast food places and see movies. She is also a friend of the twins. Rachel enjoys science class, but her favorite class is English. She enjoys reading, particularly science fiction, and spends many a night curled up in an armchair with a book in the light of a shaded lamp.

Raja, age 14.

Raja enjoys science, particularly designing and running experiments. She also enjoys her industrial arts class, where she tries to cast goblets and other objects from the Middle Ages, her favorite historical period. Raja is a good friend and frequent study partner of José, the reputed class brain.

Rajiv, age 14.

Rajiv is athletic, enjoying both soccer and dirt biking, but his first love is chemistry. His initial experiments with his chemistry set caused a few noxious events at home; his family was glad when he finally started learning how to conduct careful experiments in his eight-grade science class. He’s a good friend of Kerri, who is a frequent study partner.

Sofia, age 16.

Like her cousin Orlando and their mutual friend Jorge, high school sophomore Sofia loves to play baseball. She’s a mean pitcher and usually acts as team captain. Sofia also enjoys driving her classic 1967 Chevrolet, even though the car is constantly breaking down and badly in need of repairs. Sofia usually drives Jorge and Orlando back and forth from their baseball games.

Tomás, age 14.

Tomás is a beginning skydiver. He learned how to skydive during a trip he took with his parents (both experienced skydivers) to Australia, where the minimum legal age for skydiving is 14. He has shared his exciting experiences with his eighth-grade science class. Their teacher incorporates Tomás’s stories into class discussions about interactions and motion.