I think I understand the confusion.
The Match() function won't do what you're looking for but I'm pretty sure we can get you what you want using Tables->Join on the original tables.
4661_Tables-Join.png
This will combine the two tables by joining rows that have the same value for given columns.
I assume you have tables that look like this.
4663_Course_Grades_and_Course_Enrollment_jmp-2.png
A table with Courses and Enrollments and another table with Courses and Grades.
Then choose Tables->Join.
Select the table you want to join with.
Then select the columns you want to match and click the "Match" button under the Match Columns section.
Then click OK.
4666_Join Dialog.png
You should get a table like this.
4667_untitled_10_and_Course_Grades_and_Course_Enrollment_jmp.png
I think that's what you're looking for. It is confusing to think about matching columns and having a Match() function.
You can learn more about the Match() function here.
-Jeff
-Jeff