How to have a date appear instead of a designated value?

Good morning all,

I was curious if someone could lead me in the right direction? I was given the task by my manager to put together a spreadsheet that tallies up the amount of time someone spent in a certain classroom.

They want the amount of time, 2 or 4 to be color coded but they do not want the numbers 2 or 4 to appear in the cell. Instead, they would like the date to appear as 9/12, 9/13 etc, no need for the year.

The tricky part is that the formula I am using is adding up all the seat time so 2 and 4 work perfectly and the dates would just throw off my formula. Any ideas?

To be honest too, I used Google Sheets and now my formula for a drop down option isn't listed but appears in Excel once you type in "2 or 4"

I prefer to use Google Sheets as the principal is trying to share this with the school.

Please see attached for the Excel spreadsheet.