Final answer:
The main reason to use a level system with a token system, or token economy, is to modify behaviour effectively in settings like schools and hospitals, by rewarding positive actions.
Step-by-step explanation:
The primary reason one might consider using a level system with a token system is to effectively modify behavior in various settings such as schools, prisons, and mental hospitals. These systems, known as token economies, employ tokens as secondary reinforcers that participants can exchange for rewards or privileges. Token economies have shown significant success in encouraging appropriate behavior and reducing inappropriate actions. Behavioral management using token economies is a structured method offering consistent and immediate feedback for individuals, which is essential for effective behavior modification. For instance, when students exhibit positive behavior, they receive tokens, which can then be traded for desired rewards, such as playtime.