Autograding Excel spreadsheets

I am an MS Office instructor, and am exploring options for autograding Excel spreadsheets (and Word documents). This must be capable of dealing with variations of formulas (e.g "=B3*B4" is just as correct as "=B4*B3"). There are instances where I need to assess/grade the cell formatting, headers/footers, formulas, column widths, etc). I know that the technology exists, because I have taught courses where the publisher has provided autograding tools.
Is anyone familiar with where I may find a customizable autograding app, or available resources to create my own. I am assuming that the app would compare against a Master Solution file, and mark the differences.

Thank you for your response. My research always leads me first to Google, and when I cannot find anything in Google's results, I enter the forum with my specific needs. Unfortunately, the Google results do not seem to provide the assistance I need. I'm hoping that someone on the forum will know of, or has used a method of autograding Excel formulas, etc. It is more complex than first thought, because of all the 'right' variations of composing a formula.

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I suggest it would be easier to create if the answers were multiple choice rather than having the student manually write out the formula. That
will allow you to create a list of "correct" answers to check against.

The few examples of 'auto correct exams' I located on the internet were created in this same manner.

Logit,
Whenever possible, I use a M/C or T/F quiz questions, but there are times when I really want to use a practical approach, and let them compose their own formula. It is these practical activities with which I am struggling.

TMS,
You have identified my problem - there are indeed a myriad of solutions for any given question. Within reason, my desired approach would be able to accommodate these. I have used autograding exercises provided by the publisher, and they are able to handle variant solutions. I suppose that is why they would specifically say "using SUMIF, what is the sum of all the ...".
Maybe I'm hoping for too much, and maybe I'll have to incorporate M/C and T/F questions, but I really don't want to give up the practical questions. I believe that learning Excel is much more than theory, and works best when using practical questions.

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I don't know how you would approach your third option for answering. I suppose you could auto-grade everything but leave those
last answers to be manually graded ? Of course, the student would not immediately receive their grade.

????

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To add to my last answer ... what if you created a question that provides part of the answer. Enough so the student has not alternative BUT to provide the correct answer.

This is very simplified but you could ask : What is another way of "saying" =B3*B4 ? And the answer would be =B4*B3. Again ... simplified but it provides an example.

And I had a number of instructors who, when presenting the material, would say "You will see this again." Another means of insuring the students provide the exact answer.

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TMS and I are thinking along the same lines.

I'll stop responding at this point so as not to be repetitive.