What are the steps for allowing students to use their QR code vouchers to purchase rewards?

CritterCoin allows students to purchase rewards from your store at any time. When they do they will receive a QR code voucher. This voucher can be scanned by any teacher to confirm the purchase. Once confirmed the teacher should give the reward to the student.

1. Student signs in and purchases an item from your Reward Store. CritterCoin automatically deducts the points from their reward point balance
2. Student shows their QR code to the teacher responsible for giving out the reward.
3. The teacher clicks the "Store" menu, then scans the QR code to verify it is valid, then gives the student the reward or issue a refund.