The hammer rang once. A spark jumped off the anvil and did not go out. It waited. They followed.

It was the last Saturday of October, and the bakery on Mill Lane smelled, as it always did at seven in the morning, of yeast and burnt sugar and the floor cleaner Mr Brightwater used on the tiles before he opened.

Tara had worked there every Saturday since the start of the month. She had answered a card in the window, HELP WANTED, SATURDAYS, 16+, and Mr Brightwater had looked at her over his glasses and asked whether she could count change and smile at the same time, and she had said she would learn. She could do both now. She could also slice a loaf in the big machine without losing a finger, tie a cake box with string the way he liked, and tell, by the sound the oven door made, when a tray of rolls was nearly done.

It was not just for the money. She had wanted, at the start of her last year on the Green, to do something that was just hers. The climbing wall was one thing. This was another. There was something about standing behind the counter at seven in the morning, with the street outside still blue and empty, that made her feel like a person who belonged to a place.

But it was also for the money. And at the end of her shift, Mr Brightwater handed her a small brown envelope with her name on it, in pencil, and said, "Your first one. Don't spend it all on biscuits."

Inside was a payslip, and a note to say the money had gone into her account.

She did not read the payslip properly. She looked at the number at the bottom, which said £240, and felt a small, warm, proud feeling, like the feeling of finishing a long essay. Two hundred and forty pounds. She had earned that. Nobody had given it to her.

She was putting it back in the envelope when Mr Brightwater came through from the kitchen, wiping his hands on his apron.

"Tara," he said. "Gerry's leaving. Moving to his sister's. That leaves me nobody on Sundays." He looked hopeful and tired at once, which was how he looked most of the time. "Would you want Sundays as well? Same hours. Same pay. I'd be very glad of you."

Tara opened her mouth to say yes.

More hours, more money. It was not even a question. Twice the Saturdays meant twice the envelope. She did the sum in her head before she had finished breathing in, and the answer was obviously yes.

Devon was on the till next to her, counting the float. He was in the year above, a quiet, unhurried boy who had worked at the bakery for two years and had, Tara had noticed, a way of answering every question with another question.

"What does it cost you?" said Devon, before she could speak.

Tara turned. "It doesn't cost me anything," she said. "He pays me."

"Not in money," said Devon. He closed the till drawer gently. "In Sundays."

Tara stopped.

"I'm not saying don't," said Devon. "I'm saying every yes is a no to something. What's the next-best thing you'd give up?"

Mr Brightwater was waiting, politely, pretending to rearrange the scones.

"Can I tell you next week?" said Tara. "I want to think about it."

Mr Brightwater looked surprised, and then pleased, in a way Tara did not quite understand. "Next Saturday," he said. "That's fair."

That afternoon, at the back table of the Whetstone café, Tara laid the payslip flat between her cup and the sugar bowl. It was the first time she had really looked at it.

Yusuf was there, because Yusuf was nearly always there on Saturday afternoons, doing his maths homework with a calculator he had owned since he was eleven. He had a part-time job too, at the garden centre, and he had told Tara once that he checked his own payslip every single month, line by line, and had found a mistake twice.

"Can I?" he said, and she pushed it across.

Danya was at the next table, building something out of sugar cubes, which meant listening.

"Gross is what you earn," said Yusuf, running his finger down the page. "Net is what you get. The interesting part is every line in between." He tapped the top. "Check the hours first."

The hours said 30.

"That's wrong," said Tara at once. "I did four Saturdays. Eight till four, every time. That's eight hours a day. Thirty-two."

"Do the sum yourself," said Yusuf, and slid the calculator over.

She did. Four times eight. Thirty-two.

Yusuf pointed lower down the payslip, where a small line said Unpaid break: 0.5 h × 4.

"Did you have a break?" he said.

Tara thought. She did. Every Saturday at twelve, Mr Brightwater sent her into the back room for half an hour with a cup of tea and whatever had come out of the oven looking wrong. She had loved those half hours.

"They're unpaid," said Yusuf. "That's normal in a lot of places. Four half hours is two hours. Thirty-two take away two is thirty." He did it on the calculator to show her. "So you were paid for thirty hours. At eight pounds fifty an hour..."

"Two hundred and fifty-five," said Danya, from the next table, who had done it in his head and could not help himself.

Yusuf nodded. "Two hundred and fifty-five gross. Then this line." He pointed. Apron (one-off): £15.00. "He took fifteen pounds for your apron. Once. So two hundred and fifty-five, take away fifteen, is two hundred and forty. Net." He handed the payslip back. "Which line took that? Now you know every one."

Tara looked at the payslip. She felt a little foolish, and then, oddly, steadier. Nobody had cheated her. Mr Brightwater had written every line down, plainly, in a small brown envelope. She just had not read it.

"He's not done anything wrong," she said.

"No," said Yusuf. "It's a good payslip. You can read all of it. That's how you know."

Devon came in at four, still smelling of bread, and sat down with them. Tara told him about the payslip, and he listened, and nodded, and then he took a paper bag from the bakery out of his pocket, flattened it on the table, and drew a line down the middle.

"Not in money," he said. "In Sundays. Say what you'd be swapping."

So they made a list.

On one side, Devon wrote what Sundays would bring. Sunday was a slightly shorter shift, nine till five with the same unpaid half hour, so seven and a half paid hours. At eight pounds fifty, that was a little under sixty-four pounds a Sunday. Four Sundays a month made two hundred and fifty-five pounds. The same again as the Saturdays.

"That's a lot," said Tara. "That's double."

"It is," said Devon. "Now the other side."

On the other side, Devon wrote what Sundays were for now. Tara had to think about it, which surprised her. She had never written down what her Sundays were for. They just happened.

Sunday mornings were the climbing wall with Juno. Juno had joined in September; Tara had joined too, after reading every line of that contract, and Sunday mornings were the only time they could both go. Juno could not top-rope on her own.

Sunday afternoons were the Gazette layout. The paper went to the printer on Mondays, and it was Sunday afternoon, at this very table, when Tara and Mrs Hallam laid out the pages.

And Sunday evenings, since half term, were the university application. The personal statement. Four thousand characters that were supposed to explain who she was, which she had rewritten eleven times and still hated.

Devon looked at the two columns.

"Every Sunday of your last year on the Green," he said. "That's the swap. Not one Sunday. All of them, until you go."

Tara looked at the paper bag for a long time. It was funny how a year got shorter when you counted it in Sundays.

Marcus arrived last. He was a cheerful, slightly bossy boy from Tara's form who kept his own money in paper envelopes labelled in thick marker pen, and who had once organised a whole school trip to the coast because the teacher was ill.

He looked at the paper bag with interest.

"You've done what it costs," he said. "Good. Now what's the money for?"

"For?" said Tara.

"Give every pound a job," said Marcus. "Before it comes. Otherwise it just goes." He took the pen. "How much do you actually need?"

Nobody had ever asked Tara that, and she found she did not know. So they worked it out, there and then, on the back of the paper bag.

There was the deposit for her first term's room at university, if she got in anywhere. That would be due next August. The universities' websites said it might be about three hundred pounds. There were train fares to two open days, in the spring, about ninety pounds altogether. That made three hundred and ninety.

"That's the big stuff," said Marcus. "What do you get from Saturdays?"

"Two hundred and fifty-five gross," said Tara, who knew that now. "Two hundred and forty this month, because of the apron. Two hundred and fifty-five from next month."

"Say you save half of it," said Marcus. "Half of two hundred and fifty-five is about a hundred and twenty-seven. How many months to three hundred and ninety?"

Danya had already done it on the sugar cubes. "Three," he said. "A bit more than three."

"So by about February," said Marcus, "the deposit and the trains are covered. From Saturdays. With half left over every month for climbing and biscuits." He wrote it in a box at the bottom of the bag, and drew an envelope round it. "Envelopes first. Spending second."

Tara looked at the box. She had thought she needed the Sundays. She had assumed it, the way you assume a door is locked without trying the handle. It turned out the Saturdays alone did the job she needed done. The Sundays would be extra.

But extra was not nothing. Extra could be a better room, or fewer worries, or a holiday with Juno after exams. Devon had not said Sundays were wrong. Marcus had not said the money did not matter. They had only made it possible to see what she would be choosing.

The next Saturday, at the end of her shift, Tara stood behind the counter with the paper bag folded in her coat pocket.

Everyone who had an opinion had given it to her during the week. That was the trouble with a small place.

Juno had said, on the climbing wall, hanging from a hold with one hand, "You have to do what's right for you. Obviously. But if you take Sundays, I'm going to have to find a new partner, and I'll hate it, and I'll tell you every week."

Her mum had said that a bit of money put by was never a bad thing, and that she had worked every weekend of her own last year at school and did not regret it.

Mrs Hallam had said that she would manage the layout on her own if she had to, and had sounded as if she would rather not.

Mr Brightwater had said nothing at all. But on Thursday Tara had walked past the bakery and seen him through the window, alone behind the counter at six in the evening, sweeping up, with nobody to help him, and she had felt a small hard knot in her chest.

That night she lay awake, the way she had at the start of September, and counted Sundays. There were forty-one of them left before August, if she had done it right. She tried to imagine them all at the bakery. Forty-one mornings of slicing loaves and tying boxes. Forty-one afternoons where the Gazette got laid out without her. It did not feel like a disaster. It did not feel like nothing, either.

Then she tried to imagine them all without the bakery, and found that she could not quite picture what she would do with the money she did not earn, because she had never had it. That was the strange thing about opportunity cost, she thought. The thing you gave up was always a little blurry, and the thing you got was always sharp, with a number on it. Two hundred and fifty-five pounds was very sharp. A Sunday with Juno at the climbing wall did not have a number.

She thought about Devon's paper bag. Maybe that was what the columns were for. Not to make the blurry side win. Just to make it as easy to see as the sharp side.

He was short-staffed. He was kind. He paid her fairly and wrote every line down and gave her the broken biscuits. He was not trying to trap her. He just needed someone on Sundays.

And she wanted the money. And she wanted the Sundays. She wanted both, and she could not have both, and nobody, not Devon or Yusuf or Marcus, could choose for her. They had only helped her see.

Yusuf had read the lines. Devon had priced the swap. Marcus had given every pound a job. The ledger was on the back of a paper bag in her pocket: what she earned, what she got, what Sundays would cost her, and what the money was for.

Mr Brightwater came through from the kitchen with a tray of broken biscuits, the ones that had come out of the oven looking wrong, and set it on the counter between them, the way he always did at the end of a shift.

"So," he said. "Sundays?"

The bakery was very quiet. The street outside was going blue. Tara took the paper bag out of her pocket and unfolded it on the counter, beside the biscuits, so that she could see both columns.

 

 

(Write what Tara says to Mr Brightwater.)

 

The spark dimmed to a warm dot and settled back on the anvil. The Green was just the Green again.

Back on the Green

That Sunday Danya was offered fifty pence a time by his neighbour to walk her dog after school, every day. He said yes before she had finished the sentence.

Then he went home and drew a line down the middle of a piece of paper, and wrote football on the other side, and went back and asked if he could do every day except Wednesdays.

Afterword. The ideas in this case are gross and net pay, and opportunity cost. Gross pay is what you earn; net pay is what you actually get, after anything is taken off. The lines in between, such as unpaid breaks, one-off deductions and, for many workers, tax or pension contributions, are all written on a payslip, and reading every one of them is the only way to know your pay is right. Rules about pay, breaks and deductions differ between countries and by age, so if a line makes no sense, ask. Opportunity cost is the value of the next-best thing you give up when you say yes: a Sunday shift costs money's worth of Sundays. A budget, deciding what each pound is for before it arrives, makes it possible to see whether you need the extra at all. None of this decides for you. It only makes the swap visible. You can practise reading payslips, pricing trade-offs and building a budget in LedgerQuest.