In their first Formal Languages and Automata Theory course students find Turing machine composition challenging. In addition to the development of formal arguments, most students struggle with the idea that a Turing machine may use auxiliary Turing machines to solve a problem. This struggle is significant despite understanding that the use of auxiliary Turing machines is tantamount to using auxiliary functions in a program. This article presents two visualization tools developed to help students understand Turing machine composition. These tools are integrated into FSM–a domain-specific functional language for the Automata Theory classroom. The first is a static visualization tool that generates the transition diagram of a given composed Turing machine. The second is an interactive tool that simulates the execution of a given composed Turing machine. Empirical data collected from students is presented that suggests that the tools are well-received, easy to use, and useful.