This can be used as a center or a whole class activity with any device that has a QR code reader! I worked with each of our 1st grade classes on this, and the students loved it!! We used it as an independent center. It has 2 practices for each short vowel sound, with a total of 10 self checking QR codes! The kiddos feel so big when they check their own answers and Mom and Dad love getting to see their work come home!