The girls of Bunk 3C meet in New York City for their six-month Camp Lakeview Reunion.

When the girls of Camp Walla-Walla are in charge on Upside Down Day, they stage the greatest prank ever, deal with jealousy over one of the boy campers, and learn that running a camp is not an easy job.

Having returned for her second year at Camp Lakeview, Natalie finds herself feeling jealous of a new camper from California who seems to be even more sophisticated and glamorous that Natalie, herself.

Having left summer camp to return home, the girls from bunk 3C use a blog to keep one another informed of their struggles adjusting to sixth grade at their respective schools and to new situations at home.

During the last weeks of summer camp, eleven-year-old Alex Kim has trouble hiding a secret from the other girls in bunk 3C while also trying to meet the high standards she sets for herself in sports, relationships, and other activities.

Brinn is thrilled to work as an extra on a motion picture, but friendships are strained as Sara joins her but spends all of her time with a boy, Natalie goes into hiding after getting braces on her teeth, and Avery faces troubles at home.

Separated from her friends by different bunkhouses and activities, and worried that a classmate will reveal that she is a nerd at home, Sarah's second summer at Camp Lakeview gets even worse when an injury and an attentive boy interfere with her reputation as the camp's star athlete.

Eleven-year-old Jenna, contending with the separation of her parents and the unwanted presence of her twin brother and older sister at Camp Lakeview, is determined to make a name for herself by pulling the ultimate prank.