I would use QR Codes in the classroom for a number of activities. Whether it was literacy, math, science or any subject, QR codes get students used to using technology in a fun and creative way. The student would grab a cube and complete each of the activities as part of a daily task. I would use this in my 1st grade classroom.
This product, by It's Not Rocket Science, is a compilation of editable daily quizzes or bell ringers to start off each class period. It includes 145 days worth of assessments covering a year's worth of biology content.