The Expandable Brown family, Bob, Pat, Susie, Dad and Mother, their friends and animals, appear again. This time the story centers about son Bob and the adventures he meets with pesky Kenny, neglected Chip and the other boys who join the Caboose Club to tinker with model railroading. The boys work hard to dredge up $200 for an auctioned railroad caboose for their meetings. After all their efforts the caboose is installed in Bob's back yard and he is elected president. When someone destroys the clubroom with a hatchet, suspicion points to Chip. Then to the embarrassment of the boys, a girl helps to clear up the mystery. The general assumption that a boy's family would allow him to have a railroad caboose on family property seems somewhat incredible, but this is, after all, the Expandable Brown family who add still another member with Uncle Bill and Aunt Meg's new son before the story ends. Boys who find club membership important now will find this engrossing.