I am using Excel to assign students to different assignments during a
practical examination. I understand I can use "track changes" to monitor
changes to an individual cells. However, I will have forty individuals
participating in twelve different activities. As each person completes a
station, a number is assigned to the corresponding cell. It would be too
difficult to check each cell for the last modification time for each person.

I would like to have a cell that monitors when a change occurs within a
range of cells. This would help me in monitoring how long it has been since a
student has completed an assignment. Any suggestions would be useful.