Ok - I’ve looked at this picture intensely and for the life of me can’t see what time it is.
He must have cut a hole in the box.
It would have been less trouble if he had used one of the see-through types of "pencil boxes".
I've never heard of the things until recently. They didn't have those back in the days when the miles long walk to school was all uphill, coming and going, and we had to fight blizzards every day just to get to school and back...