Draw What They Are Seeing.

Daydreaming is not necessarily a waste of time. For example, it can be quite useful for giving a person time to manage their emotions through getting away from a source of emotional difficulty. Daydreaming also permits the creative elements to fuse and produce more easily without the conscious self (a person's usual, everyday self), ego, and judgment in the way. Part of the creative process involves putting those aspects aside so that the creative forces can flow freely.

Adults often do not feel comfortable calling it daydreaming, however, so we invented another, more mature word -- preoccupation.

Children often daydream, and when a student is daydreaming in class, instead of saying to stop it, a better approach is for the teacher to ask the student to write or draw what they are seeing.