Cognitive coaching research?

I am simultaneously taking cognitive coaching at the same time that I am completing this class.  I just had the idea to combine the two!  I wonder if I can use the coaching with my mentee to also formulate the basis of my action research topic?

I haven't read all the articles on AR as of yet, so I wonder how different the process is from scientific research that I am familiar with?

My question would be:
How does cognitive coaching affect (effect? I'll have to look that up) student achievement?

Variable:
cognitive coaching

Controls:

Here is where it gets kind of sticky.  Need to have a group of students that we have a base line before coaching and after.  This won't happen because we just switched semesters and we have a whole new group of kids.

Same novice teacher
Same mentor

I wonder if we could use a baseline of data that was collected last semester (student achievement) from the same course that she is also teaching this year?  Still, different students.

I'll have to read up on that while I'm getting my hair done today.