Arthur's wrong guess about the identity of the secret admirer sending him valentine messages leads to teasing by the other children, but clues in additional messages allow him to get his due.
D.W., Arthur's little sister, tells all about what it is like to be in preschool, including essential information about such topics as bathroom breaks, storing things in a cubbie, and sharing at play time.
Arthur is unhappy about going on vacation with his family, but he shows them how to make the best of a bad situation when they end up stuck in a motel because of rain.