Madeline Dare has traded in the drudgery of living in backwoods Syracuse, New York, to work as a teacher at Santangelo Academy, a boarding school for emotionally disturbed teenagers in the Berkshires. Behind the ornate gates of the academy, she finds a disturbing realm where students and teachers must follow the dean’s bizarre therapies. From her first day, Madeline doubts Dr. Santangelo’s credibility, and she’s not afraid to voice her concerns.

...

Miss Clavel puts the girls to bed after a wonderful day at the fair and discovers that Madeline are her friend Pepito were left behind. The Gypsy Mama rescues them from the ferns wheel and makes them a pan of their travelling circus. Madeline and Pepito send a postcard to Miss Clavel and she trails them to the city on the postmark. The Gypsy Mama, afraid to lose the children, dresses them as a lion and they search about for someone to help remove...

The Spanish Ambassador and his family have moved to London. Miss Clavel and the girls are invited to London for Pepito's birthday party and they buy a retired horse from the Royal Stables as a gift. Madeline and Pepito are riding the horse in the courtyard when it jumps the fence and joins the Queen's procession! That night, after touring the city in search of the children. Miss Clavel tucks everyone into bed. But the poor horse hadn't eaten all day...

Madeline falls into the Seine and is rescued by a courageous dog. The girls take home the collarless mutt and name her Genevieve. Lord Cucuface, the President of the Board of Trustees, insists that dogs are not allowed in the convent and his chauffeur takes Genevieve away. Miss Clavel and the girls search the streets of Paris for her but return to the convent disappointed and disheartened. Miss Clavel investigates a noise in the night - it's Genevieve!...

The girls are looking forward to a big costume bash at Pepito's house. But a week or so before the festivities they all come down with chicken pox and are quarantined in the Old House. Then, when Dr. Cohn declares that they have recovered just in time for the party, Madeline helps everyone create costumes that incorporate their remaining "spots".

At the Old House - and all over the neighborhood - people's hats, gloves and scarves are missing. Madeline and Pepito work with Detective Moreau to find the perpetrators, then finally discover that the "thieves" are some altruistic magpies who are distributing the warm clothes to the homeless in the park.

The circus has been cancelled because Monsieur Funnybones, the world's shortest clown, has lost his ability to laugh. When the forlorn performer shows up at the Old House disguised as a chimney sweep, Madeline teaches him that being tall is just a state of mind.

After being evicted from the opera for barking along with her favorite arias, Genevieve is dog napped by an impresario who sets her up at a dinner theatre. When Madeline finally catches up with her talented canine, Genevieve, now a star is reluctant to go home because she is still embarrassed about the incident at the opera. It is up to Madeline to convince Genevieve how much she is missed at the Old House.

The Old House, sorely in need of repair, is condemned and the girls are forced to move to a small apartment where their snooty neighbors hate kids and dogs. But just before the wrecking ball destroys their beloved abode, Madeline enlists the aid of the ladies of the Historical Society, who help get the Old House renovated to perfection.

Just in time for Easter, Madeline updates the old hat belonging to Bon Bon, the milk horse. But then an enormous gust of wind sends the hat flying across town, into the shop of a struggling designer, who attempts to market it in time for Easter.