Life is full of challenges for thirteen-year-old Liza. She is already having trouble coping with the death of a local homeless man when she learns that her family's apple tree will need to be chopped down. If that wasn't enough, the new principal at school keeps blocking her attempts for a positive outlet by refusing permission for every project that GRRR! (Girls for Renewable Resources, Really!) and BRRR! (Boys for Renewable Resources, Really!) proposes. Liza starts to feel like she needs to create change in her world without seeking permission. When she chooses the school grounds as the site for her latest endeavor, she may have gone too far.
Jessica loves her yearly backpacking trip with her father, but this year everything has changed. This year Jessica has to share her vacation with her new stepmother and her spoiled new stepsister, Amy. Jessica tries to salvage her holiday by sneaking off for a day hike alone, but Amy follows. Jessica is certain that Amy will ruin the day. Amy rises to the challenge of the rigourous hike and Jessica learns that Amy is not as spoiled as she thought. When Amy is injured and night falls, Jessica must face the challenge of hiking through bear country in the dark.
When Trevor, Nick and Robyn visit the Royal Tyrrell Museum, Robyn is inspired to raise funds for a dinosaur dig that will close soon if it doesn't find funding. The kids are caught up in another mystery when a chain of suspicious events, including the disappearance of important fossils and a fraudulent discovery at the dig, leads them to wonder what's going on. Is the new visiting scientist behind the fraud, or did Robyn's enthusiasm to save the dig lead her astray?
When Renata is chosen to play the lead role in the school musical, students who used to ignore her start saying hello and congratulating her in the hall. She is happy until it becomes evident that Karin, a wealthy girl who expected to get the lead role, will go to great lengths to ruin Renata's reputation.
Dorf is all about skateboarding and so far that's worked out fine. But now that he's in a new city, the terrain has changed. He's no longer free to skateboard where he wishes, school is more difficult, and his passion for skateboarding garners him the nickname and reputation of a freak. With daring stunts he gains the grudging respect of local troublemakers, but he needs to tap into another kind of courage to effect real change.
Jim, Mickey and Lisa belong to a secret club called the Sewer Rats. Every Saturday the Sewer Rats reign supreme in paintball wars held in the city's storm drain system. The new kid, Carter, wants to join, but Lisa doesn't want him in the club. When Carter is hurt in his first paintball war, Jim and Mickey suspect that Lisa planned the accident. They try to confront her, but she runs into the tunnels just as a rainstorm begins. Jim and Mickey have to get Lisa out before the tunnels fill with water.
At first Kaz intends to help the old lady who's fallen in the park. But then he starts thinking about how he never gets what he wants. The next thing he knows, he's running away with her purse. The purse contains only five dollars and a battered watch. When Kaz learns who the old woman is and where the watch came from, he begins to understand consequences in a new way.