Students solve 20 problems involving the Properties of Definite Integrals, sum the answers, then scan a QR code to check their sum in this engaging, self-grading, no-prep Sum It Up Activity that uses QR Codes. Not only will this worksheet challenge their ability to answer questions about definite integrals, but it also injects an exciting twist by requiring them to use their devices to scan a code to check their answers. Finally, a fun reason for students to use their phones in class!The workshe