The students of the 121 Express are infamous for bad behavior and Lucas knows his role on the bus will determine his social standing at his new school. Lucas is tired of being one of the nerds. When he attracts the negative attention of the cool troublemakers, he saves himself by teasing another kid. His ploy works and soon Lucas is right in the center of the mayhem on the bus. He loves his new found popularity, but when the fun and games push the bus driver to a nervous collapse and hospitalizes an elderly lady, Lucas begins to question his choices.
As much as life has irrevocably changed since the death of his father, much has stayed the same for Cam. He's always had a great deal of responsibility around the house, but the burden is heavier now in combination with the load of grief he's been carrying. After the man who was driving the truck that killed his father turns up at the end of the driveway, Cam feels pressure to keep his family safe as well. He starts to see the man everywhere: at his work, in stores, at his sister's school. Cam needs to know what the man wants from his family, and he starts following his father's killer in search of answers.
Turk needs cash, but he's allergic to his own sweat so getting a job is out of the question. Then he makes a discovery: Girls love dogs. Turk's friends will do anything to meet girls. Turk starts a dog walking business. His friends walk the dogs and Turk collects half the money. In an attempt to impress dog-loving Carly, Turk brags about his business in front of the school tough guy, Chuck. When Chuck learns the true nature of Turk's business and wants in on the action, Turk worries that he will lose his business and Carly's respect.
While volunteering at the local zoo, Robyn, Nick and Trevor learn that grizzly bears are being poached and their gall bladders removed for use in alternative medicine. Always ready to solve a mystery, the kids set out to find the poachers. Bear is not only big game, they learn, but big money to poachers. The stakes are high and the suspects many, as the kids head into their most dangerous adventure yet.
Trevor, Nick and Robyn are ready to solve another mystery. When bobsledder Josh Gantz is accused of deliberately injuring a fellow competitor, he runs the risk of being thrown out of the sport -- right before the World Cup. Courtney Gantz asks Trevor, Nick and Robyn to help clear her brother's name. Can they find out who framed Josh? What is the meaning of the strange coded messages they keep finding around Olympic Park? Who eats orange bananas, anyway? The kids must unearth the clues in a race against time, before Josh's championship dreams end up on ice.
Fourteen-year-old Matt has only one goal in life: to become a hermit. He has no use for school, but he loves the solitude of the forest. When he hikes up to the cabin he built for himself, he discovers a mysterious stranger named Forrest has moved in. At first Matt doesn't connect Forrest's appearance with the rash of local robberies. Forrest seems to be the perfect hermit, and he teaches Matt the skills he needs to achieve his goal, including how to hunt with a crossbow. But when Forrest tries to kill an endangered Roosevelt elk, Matt questions the ethics of his new friend. When Matt discovers a stolen rifle in his cabin, he finds himself trapped in a dangerous situation.
Trevor, Robyn and Nick decide they have a mystery to solve when Trevor discovers a suspicious looking young man snooping around. They learn about missing research involving the use of carob beans to aid in cancer treatment-potentially valuable information. With a shady looking grad student, a bitter activist and an employee of a medical research firm to deal with, our amateur sleuths are faced with their greatest challenge yet.