I really like the premise of this questioning method because I feel that it works the students toward higher levels of critical thinking. Here is a brief description of the HRASE hierarchy, as shown by Clough (2007, pg. 1):
History - Ask questions that relate to students' experiences
What did you do when...?
Relationships - Ask questions that have students compare ideas, data, activities, etc.
How does this compare to...?
Application - Ask questions that require students to use knowledge in new contexts
What safety issues could this solve?
Speculation - Ask questions that require thinking beyond the given information
What would happen if you...?
Explanation - Ask questions to get at the underlying reasons or processes
How does that work?
Clough, Michael P. (2007). What is so important about asking questions? Iowa Science Teachers Journal, 34, 1.