By using one QR code across many lessons, you can significantly cut down on your printing needs. One answer sheet can be used for any number of tests. You can also use a QR code in classrooms to send students to an online test that has been created for them by their teacher. This is especially useful when students are absent and need to take a test at home.
QR codes are also useful for distributing homework assignments and tests. Instead of giving out papers with the assignment on it, you can scan the QR code on the paper and direct students to their assigned work online. When it comes to grading tests, you can use a QR code to print out the results of each student's work without having to scan each paper separately!