Are you still worried about your children’s math grades? This Roller digital teaching stamp will make it easy for kids to practice addition and subtraction. The seal can freely combine numbers to meet mathematical addition and subtraction within 100. Rotate and adjust column types, you can adjust 10 different queue sides, and you can quickly prepare math problems for your child at home. You also can quickly complete the quiz simply by scrolling through the math questions. Moreover, this addition and subtraction math stamp is small and exquisite, it can be reused many times by adding ink, the stamp is clear, and it will not fade after drying. Keep the kids busy and get yourself a moment of quiet when they need it. So, it’s a great gift for our kids and even for parents. Get it now!