Outdoor Girls Books in Order

Betty's visiting uncle helps launch a summer cruise aboard the motorboat Gem. As Betty and her friends prepare to explore Rainbow Lake, mysterious reports about Elm Island add a puzzle to their plans for boating and adventure.

Mollie's new motor car gives the Outdoor Girls a chance to explore beyond Deepdale. An encounter with a girl who falls from a tree leads toward further mysteries, including a supposedly haunted mansion in Shadow Valley.

The Outdoor Girls plan a winter stay at a lumber camp, combining skating with time together away from home. A property dispute and hurtful remarks about Amy's unknown background bring personal worries into their outdoor holiday.

Grace's brother Will disappears, turning the Outdoor Girls' planned Florida visit into a search for their friend. Their motorboat journey through unfamiliar waterways brings them near labor camps and people who may know where he has gone.

Betty, Grace, Mollie, and Amy form a club for a summer of walking and camping. The discovery of a five-hundred-dollar bill with a troubling note adds a mystery to their first plans for independent outdoor adventure.

The Outdoor Girls settle into a seaside cottage for a summer at Ocean View. Finding an iron box buried in the sand sparks questions about its contents, while mysterious men nearby give their discovery a more troubling significance.

Betty, Mollie, Grace, and Amy prepare for another summer outing, this time to Pine Island. A runaway car starts their adventures with a mishap, while the search for an elusive cave gives their explorations a purpose.

As friends enlist for World War I, the Outdoor Girls look for ways to help. Knitting for soldiers and planning Red Cross events turn their usual activities toward wartime service, mixing friendship with worries about those heading away.

Betty, Mollie, Grace and Amy continue their wartime work at the Hostess House while worrying about friends leaving for the front. Helping an injured elderly woman brings another family's long separation into their daily responsibilities.

A stay at Bluff Point offers the Outdoor Girls a break from their wartime duties. News of a wounded friend and other troubles shadows the holiday, testing their ability to support one another while they wait.

A professor's quick action saves the Outdoor Girls from a falling tree, drawing them into concern for his troubled life. Their trip to Wild Rose Lodge brings further uncertainty while they await friends returning from the war.

Betty's mother inherits a western ranch, and the Outdoor Girls travel there eager to ride and explore. Unsolicited purchase offers raise questions about the property, while a struggling prospector and his daughter draw the friends' concern.

The Outdoor Girls plan to stay in a lakeside shack, only to find it destroyed. Improvised camping brings nighttime disturbances and a meeting with an impoverished older woman whose story adds another mystery to their holiday.

On Cape Cod, the Outdoor Girls meet Sally Ann, a lighthouse keeper's ward forced into unpaid work. Helping the proud young woman proves difficult, especially when the friends overhear signs of a plot involving her.

With Mollie now leading the Outdoor Girls, a birthday dog brings excitement to the group. When pets disappear across Deepdale, a visit to Foaming Falls and a supposedly haunted house introduce further questions and unsettling sounds.

A coastal cruise aboard the Liberty brings the Outdoor Girls back to Sally Ann, whose relatives threaten her happiness at home. Meeting another young woman desperate to escape her companions adds a second problem to their journey.

A quiet vacation at Spring Hill Farm turns into a treasure hunt for the Outdoor Girls. Their holiday mixes friendship and country life with the search for hidden answers, drawing the group into another unexpected adventure.

The Outdoor Girls welcome new members and head west to New Moon Ranch for riding and exploration. Meanwhile, Mollie's friends wonder whether she will choose Roy Anderson or Clem Field, adding romantic uncertainty to the outdoor adventures.

Stella Sibley leads the Outdoor Girls on a two-week hike to visit their married friends. A theft of family heirlooms and increasingly threatening encounters along the route turn their planned outdoor holiday into a dangerous mystery.

The Outdoor Girls' flying lessons bring them close to Stella and a new invention for aircraft. When trouble surrounding its sponsor leads to a theft, the friends must investigate the people trying to take the mechanism.