The book deals with a difficult area of the Czech spelling, which is the words with the pre-fixes s- and z-. The story is about a cowardly boy Standa, who meets a new pupil.
The text is full of words with prefixes s- and z-, so the children consolidate their use. Part of the book is an illustrated overview of the rules of writing these words, rules for writing prefixes s- and -z-, a list of insidious pairs and triplets, and an illustrated table that helps in decid-ing which prefix to write in the word.