A little knowledge can be dangerous.

Ben Derby is convinced his spring vacation has been ruined by his social studies teacher's assignment -- a week's volunteer service at a community charity. Haunted by something dark in his own past, Ben chooses to work at Sidewalk's End, a day care center for children of the homeless.
When Ben believes he has seen one of Sidewalk's End kids being abused by his mother at a grocery store, he is frustrated by his inability to get the authorites to act to protect the child.

Ben concocts a daring plan to rescue the boy, but soon discovers that good intentions aren't always enough --- and that taking matters into your own hands can be dangerous