Addition and subtraction up to four digits with no regrouping. There are 22 problem cards with QR codes only. Students will scan QR code and the problem will show up on their device horizontally. There is also place value paper for the student to set up the problem vertically and work it out. After the scoot is completed, I would have each student bring up their card, scan it, write down the problem, and show the class how to work it out. The students can check their paper with a crayon at their desk.