Liza and Bill Roberts are twins, and Jed is their older brother.  Many of their mysteries take the form of treasure hunts, some set by their own family.  It sort of became a family tradition after an ancestor of their set a treasure hunt for his children that ended up taking generations to solve.  Some of the treasure hunts involve word games and codes that readers can solve alongside the Roberts children, but others are just for readers to read about the adventure, with no way to solve the clues themselves.

Although the three Roberts children enjoy working together to solve their mysteries, they do not always get along perfectly.  Sometimes, the two boys pick on Liza, and both Liza and Bill have tempers.  Bill in particular has trouble controlling his temper, even breaking things when he loses patience.  The children’s grandparents say that this is a family trait and that their father was also like that when he was young.  They lecture the children when they misbehave and praise them when they do well.

Jed’s real name is John (after their grandfather’s brother), but for some reason, he called himself Jed when he was little, and the nickname stuck.

The last three books in the series all take place over the course of a single summer when the children visit their grandparents’ vacation home on Pirate Island.

The author of this series, Peggy Parish, also wrote the Amelia Bedelia series.

Books in the Liza, Bill, and Jed series:

keytreasureKey to the Treasure

Liza, Bill, and Jed solve a treasure hunt left by their great-great-grandfather which his children were never able to solve.  It leads to objects that were left to him by a Native American woman.

clueswoodsClues in the Woods

Someone is stealing the food scraps that the children’s grandmother was saving for a neighbor’s pets.  Who could it be?

hauntedhouseThe Haunted House

The Roberts family moves to another house which people say is haunted.  Then, they receive a series of mysterious messages and surprise presents.  Who is leaving these things?

pirateislandPirate Island Adventure

The kids visit their grandparents’ vacation home on Pirate Island and solve a treasure hunt that their grandfather’s brother created years ago.  He was inspired by the treasure hunt that their ancestor created.

The Mystery of Hermit Dan

This adventure comes immediately after the events of the previous book, while the children are still visiting with their grandparents on Pirate Island.  This time, they investigate the mysterious man known at Hermit Dan, who generously gives food to the people on the island but keeps mostly to himself.  People say that his ancestors were pirates, and the children see him burying a mysterious box.

cougarislandThe Ghosts of Cougar Island

This book immediately follows the two previous books in the series.  The children learn the mysterious ghost story that surrounds Cougar Island, which is very close to Pirate Island, and decide to investigate.  They soon discover that Cougar Island isn’t as abandoned as everyone thinks.