In a course that I need to describe, there are 4 exams with the following schedule:
1/1/2012 Exam 1
1/8/2012 Exam 2
1/15/2012 Exam 3
1/22/2012 Exam 4
To express this, I used
There was a one-week span between each assignment.
However, I am not sure if this sentence expresses the situation well? Any suggestions?