Place A Checkmark With A Single Mouse Click?

I have a worksheet that I use to monitor the progress of student interns. They are assigned 20 different tasks and recieve 5 points for each task they complete, for a possible total of 100. In my worksheet, I record their progress and maintain a running total. I do this by simply inserting the number "5" by each cell containing each task. Instead of inserting the value, what I'd prefer to do is simply place my cursor, click the mouse button, and have a formattable check mark appear with a hidden value of "5". I'm simply trying to create a snazzy interface. Do I want too much? Or is it actually possible to do this?