Black ice (freezing rain)
You consciously let participants make mistakes.
Create a task with a high potential for error.
Warning "Attention: freezing rain. Risk of slipping!"
Participants perform the task.
Create another task, which makes the mistake made earlier evident.
Make clear causes and effects.
Let find solutions.
Computer with standard software.
Align the date on the right side of the page in the word processor using spaces.