The school has a say
At other occasions a gift is right when the recipient likes it. When school starts it is right when it matches the school's list and arrives in time.
The list of supplies
Ruling, square size, triangular or round: an exercise book with the wrong ruling stays unused in the school bag on the first day
Five givers, one school cone
Without coordination two of them buy the same alarm clock, and the colouring pencils are missing altogether
The packing evening
The school cone is filled the evening before the first day. Whatever arrives after that is too late
The school bag
It is tried on at a specialist shop, not bought online. Nobody may get it twice all the same
For you as the shop, starting school is a fixed date that a whole year group has every year. A list that already carries the school's requirements brings the relatives into your shop instead of sending them off with a slip of paper.