After a fight at school leaves Marcus facing suspension, Marcus's mother takes him and his younger brother, who had Down's syndrome, to Puerto Rico to visit relatives they do not remember or have never met, and while there Marcus starts searching for his father, who left their family ten years ago and is somewhere on the island.

Sara's fourtheenth summer was turning out to be the most confusing time of her life. Up until this summer, things had flowed smoothly, like the gliding swans on the lake. Now she wants to fly away from everything - her beautiful older sister, her bossy Aunt Willie, her remote father, and most of all, herself. But can she fly away from Charlie? Sara loves her brother so much, and in a way she can't understand, though sometimes she can't stand his neediness....

The summer that Hattie turns twelve, she meets the childlike uncle she never knew and becomes friends with a girl who works at the carnival that comes to Hattie's small town.

Ten-year-old Liam and his two younger sisters, precocious third-grader Dakota and second-grader Izzy, who has Down syndrome, face the possibility of losing their beloved dog, Cupcake, who keeps urinating on their apartment's carpet.

Sixth grader Maggie feels burdened by her seven-year-old sister Hannie, who is slightly brain-damaged and believes that a toy unicorn has magical powers, until one afternoon a crisis shows her how special Hannie is.

While helping police officers Esther and Lon investigate a suspicious death at her group home, nineteen-year-old Sal Miyake, who is mentally challenged, gains insights into herself and makes new friends.

After the death of his grandmother, who held the family together, teenage JP is left with a mentally challenged father and a mother who seems ineffectual and constantly sick, and he feels everything sliding out of control.

Right before winter break, fourteen-year-old Molly Rosenberg reluctantly volunteers to participate in Santa Monica's annual homeless count, just to get her school's community service requirement out of the way. But when she ends up meeting Red, a spirited homeless girl only a few years older than she is, Molly makes it her mission to reunite her with her family in time for Christmas. This turns out to be extremely difficult -- because Red refuses...

Carly learns a lot about Alex, her mentally disabled older brother, as he trains for and competes in the Special Olympics.

In the late seventeenth century, fifteen-year-old Kit, driven to desperation by the starvation of one brother and mistreatment of his own simple-minded twin, realizes his dream of becoming an apprentice in London but feels drawn by duty to return home to Essex.