QR Code Student log out and log in -- 2

I need a QR code list generated that a teacher can scan when the student leaves to go to the toilet and then scans when they come back. The time of exit and entry is added to a shared excel sheet. All I want the educator to have to do is scan the code twice. It would be great if this could be added to an ID card in the future like a bar code. We have an ID card printer. This is to keep track of students movements out of the classroom for safety etc. This is a very simplistic job and should not take someone with experience to set up. I am limited by not being able to put addins in excel and the document link is on sharepoint, but you will have to use it to set up