The new exhibit at the Philadelphia children's museum, Let's Play, isn't meant to be shocking-but when one of the installers is zapped with a fatal electrical charge, it's up to Nell to put her detective skills on display.

Capitol City's Natural History Museum is haunted - or at least that's what someone wants people to think. But Wilson Kipper, son of the museum's head paleontologist, knows better. When the mysterious occurrences go from spooky to dangerous, the museum is forced to close its doors. Can Wilson and his friends get to the bottom of things, or will the Natural History Museum be closed for good?

When the plans for the prototype of a failed flying machine go missing from the Air and Space Museum's archives, Amal's father, the assistant archivist, is blamed. No one suspects a crime has been committed - except Amal and her friends. With her father's job on the line, it's up to them to track down the missing plans and get to the bottom of the museum mystery.

There's a vandal in the Capitol City Museum of American History, and he or she is intent on defacing priceless artifacts. Raining Sam, the son of the Head of Educational Programs and local Ojibwe tribe member, is determined to get to the bottom of things before anything else can be destroyed. But when Raining himself is considered a suspect, he and his friends must race against the clock to unmask the real culprit and solve the museum mystery before...

A priceless sculpture has been stolen from the Capitol City Art Museum! But with insurance money to cover the theft and build a new education wing, no one is overly worried about getting the missing art back. The only ones who seem concerned with solving the case are Clemetine and her friends. Can these determined detectives get to the bottom of the art-museum mystery before it's too late?

"As the director of Barton Farm, a living history museum, Kelsey Cambridge is underpaid and underappreciated, but she loves every minute of it. Determined to keep the struggling museum open, she plans to impress Barton Farm's wealthy benefactress, Cynthia Cherry, with a Civil War reenactment on the farm's grounds. Unfortunately, the first shot in the battle isn't from a period soldier. It's from Cynthia's greedy nephew, Maxwell, who fires a threat...

When Clementine Wim spots a famous painting being carried away from the Capitol City Art Museum, she knows something is wrong. But when she arrives at the museum, the painting is hanging right where it should be. No one believes what Clementine saw: not even her mother, an assistant curator at the museum, or her friends. It's up to Clementine to convince the others and determine fact from forgery before it's too late.

A shipment of dinosaur bones meant for a new exhibit at the Capitol City Natural History Museum has disappeared, and so have the five paleontologists who were working late at the museum, including Wilson Kipper's mother--so Wilson and his museum friends set out to solve the mystery.

When the spacesuit of famous astronaut Sally Ride disappears from a traveling exhibit, Amal Farah, daughter of the Air and Space Museum's archivist, and her three friends, are determined to find the culprit before the exhibit is cancelled.