It was the Monday afternoon of the last week before Christmas break in the late 1970s.
By tradition, although not formally linked to any church, we had an annual advent service at the local Catholic Church, St Mary’s, which was only a stone’s throw from the school gates.
The whole school would attend, the first years at the front and sixth formers at the back.
Some of the singing was OK, but most of us still found it a chore as it was the same each year.
Three of us were together in a row; Mary and Trish, like me, would rather have been anywhere else.
We had to leave our bags in school to pick up after the service, but Mary realised she had a pen in her coat pocket.
She opened the hymn book stored on the shelf in front of her and drew noughts and crosses frame at the bottom of one the pages, then she put a nought in one corner.