Canteen coupons are a means of payment for buying food & drinks at the school canteen.

This coupon is already valid when entering the 2019/2020 school year. all school residents can use this coupon to shop at the canteen. This coupon is only valid in SMA 15 canteen, not valid at other places or schools. we have to use canteen coupons because it makes it easier to manage finances after the transaction, because money is not directly taken by the seller but processed by the school first. to use the coupons we must first exchange to the teacher with the nominal number we want, then we can shop using the coupon.

So we can conclude that to make a transaction in the canteen, we must exchange the money with the coupons, to ease the finace managing afterwards.