‘You’re right,’ she said. ‘I do like it.’

One day they hired bikes and took a break from WW1 and just cycled round the countryside.

‘I feel so free,’ Sophie said to herself as they cycled past a big blue lake. It seemed like a pretty sophisticated thing to say, so she said it again, out loud. Ludo Hall heard her and gave a funny look, but she didn’t mind.

That day they ate their packed lunches at a couple of picnic tables near a campsite in a little beech wood dotted with yellow aconite. Rhiannon dropped her Dairylea triangle on the ground under the table and bent down to fetch it. When she sat up again she was laughing.

‘What’s the joke, Rhiannon?’ asked Mr Dempster.

‘Nothing, sir,’ said Rhiannon, unconvincingly. ‘I was just laughing coz I dropped my cheese, and now it’s all covered in twigs and things.’

When Mr Dempster went over to the other table to discuss the route with Mr Raddock, Rhiannon explained in a whisper to Sophie and Flick what it was she’d really been laughing about. Mr Dempster was wearing tight lycra cycling shorts: apparently, when he sat down, his penis bulged up between his legs. ‘Wait till he comes back, then pretend to drop something and have a look,’ Rhiannon advised.

‘I actually already noticed it when he was just standing up at that junction earlier when we stopped for our drink,’ said Flick excitedly.

‘I think it’s a big one,’ said Rhiannon.

‘Do you think he has to get it measured when he buys those shorts?’ Sophie joked, and was gratified by the other girls’ approving laughs.

‘Sssh, he’s coming back,’ hissed Rhiannon. ‘Get ready to drop something.’

But Mr Dempster had only come over to tell them it was time to eat up and get back on the bikes.

* * *

In the evenings, the teachers took it in turns to cook. The children found this hilarious, especially when it was clumsy old Mr Mably’s turn. (In fact, he managed a passable spaghetti Bolognese.) The culinary star of the week was Mr Dempster: his coq au vin scored highly, mostly on the grounds that it contained alcohol in the sauce and ‘cock’ in the title.

Sophie was one of Mr Dempster’s kitchen helpers for the coq au vin meal, so once they’d finished eating her chores were over for the night. While the plates were being washed up she slipped outside to catch the last of the sun. It was very low in the sky, blazing through the thin leaves of the young hazel trees that lined the river banks. The water flickered with a richer shade of gold. Sophie squatted down on the bank and stared at the river until she could see the trout. They were always there, only you had to wait for your eyes to catch up.

‘Sophie?’

It was Mr Dempster.

‘Everything okay?’