When Samantha "Sam" Archer and her friends in the nature club arrive in Yellowstone Park on a school trip, they find that the park superintendent's son may have been kidnapped.

While their sixth-grade class is on a field trip to Everglades National Park, James "Gum" Shoo and his friends find a suspicious park ranger and a gang of poachers.

The Haunted House ride at Fun City is rumored to be haunted by the ghost of someone who died there, and when Samantha "Sam" Archer and her friends get trapped inside they need to find the truth.

Edward G. Garrison, who is known as Egg, goes on a Science Club field trip to the zoo, and when everybody arrives, they discover that the Island Foxes, an endangered species, has been stolen, which leads Egg and his friends to try finding the missing animals.

When a series of accidents and other strange happenings at the Capitol City Natural History Museum lead to rumors that the museum is being haunted by the ghost of a Pterosaur, ten-year-old Wilson Kipper and his friends set out to solve the mystery.

While on a field trip, James "Gum" Shoo's art class unexpectedly finds a forgery at the museum, and it is up to Gum and his friends to solve the mystery and find the culprit.

When the plans for the Bat-Wing, a historical aircraft, disappear from the Capitol City Air and Space Museum, eleven-year-old Amal Farah's father is blamed, and it is up to the four young friends to solve the mystery and save her father's job.