But the teacher’s abrupt remark had knocked her temporarily off balance. She grabbed the beautiful parcel in its bright scarlet and green Christmas paper and thrust it into the teacher’s hands. And then she said something so sensible that afterwards she wondered what had put it into her head. ‘Good morning, Miss Cracknell. I’ve brought you a Christmas gift from my grandmother, because she’s an awful good cook and she said teachers were busy people and didn’t get much chance to do fancy cooking. And we both hope you enjoy them . . . so happy Christmas, Miss!’

Miss Cracknell’s mouth opened and closed but no words came out. Tess waited for perhaps ten seconds, then turned on her heel. She had taken two steps away from the front door when Miss Cracknell croaked one word: ‘Wait!’

Tess turned back in time to see her teacher’s brown-clad figure disappearing into the darkness of a short hallway. What on earth was the woman about to do? But she was back within seconds, her face rather flushed. She held out a small screw of paper which, in her turn, she thrust at Tess. ‘Seasons greetings,’ she said stiffly. Then she shut the door firmly, leaving Tess staring at its green-painted panels. She was turning away, wondering what was in the screw of paper, when another voice spoke.

‘What the devil are you doin’ here, Tess Williams?’ it said disagreeably. The speaker stopped beside her and peered into her face, and Tess recognised a girl in her class at school. ‘Hopin’ to curry favour wi’ old Clackem? I seen you walkin’ up and down the road, pluckin’ up the courage to go creepin’ up to her front door. What did she give you then?’ She laughed hoarsely. ‘A saccharin tablet?’

‘Oh, shut your gob!’ Tess said. She couldn’t bear Matilda, who was fat and spiteful as well as being the stupidest girl in the class and one of Marilyn’s chief hangers-on. ‘What makes you think she gave me anything? I was only delivering something for my gran.’ She turned and began to hurry down the street, determined not to get into an argument with a girl she thoroughly disliked, and though Matilda followed her for a few yards she soon gave up when Tess broke into a run. Tess had pushed the screw of paper into her pocket as soon as she heard Matilda’s voice and decided to leave it there until she reached the flat once more, reasoning that it was too small to contain anything really interesting. As she unlocked the door and began to climb the stairs, she fingered the little packet, thinking wistfully how nice it would be if her teacher had pressed a couple of bob into her hand, but whatever was inside the tissue the most cursory exploration with her fingers told her that it wasn’t coins. In fact, it felt like nothing so much as a couple of pebbles. But even as she pulled the packet out of her pocket she realised that Clackem was unlikely to play a practical joke on her. You only did that to your friends.