Mr Meredith stood behind us and placed one hand on my shoulder and one on Aiden’s.

‘How lucky are we, class?’ he said over the tops of our heads. No one said anything, but then I guess it was a question that didn’t need an answer. ‘We don’t just have one student joining us today, but two.’

The class gazed at us. It would be good to report that they weren’t too interested, that they were staring out of windows or picking at fingernails, but the simple truth is they were staring at us like we were from another planet. The temperature of my face ratcheted up another couple of degrees.

‘Not only that,’ continued Mr Meredith, ‘but they are identical twins.’ There was wonder in his voice as if we were all witnessing a miracle. ‘Who can tell me about identical twins?’

A girl in the front row put her hand up, but Mr Meredith ignored her. I guessed she always put her hand up, the class know-it-all who made everyone else feel small. I’d seen old movies where this happened. A boy towards the back raised his arm, but it was slow and unsure in its journey. Mr Meredith took his hand from my shoulder and it appeared in front of my eyes, index finger pointing.

‘Yes, Daniel,’ he said.

‘Two children born from the same mother who look like each other,’ he said, but his voice was cracking and unsure. There was silence and it was obvious he was expected to say something else. ‘At the same time,’ he added.

‘Very good, Daniel,’ said Mr Meredith. ‘Excellent.’

The girl at the front still had her hand up. Mr Meredith’s sigh played across my cheek.

‘Yes, Charlotte?’ he said.

Charlotte sat up straighter, jiggled her shoulders as if making sure they both lined up correctly.

‘Please sir,’ she said. ‘Identical twins are from one zygote, which splits and forms two embryos, which means that these two can’t be identical twins because you can’t have identical twins of the opposite gender. So they must be fraternal twins who come from two separate eggs fertilised separately.’

There was a sprinkle of laughter. I guessed it was at the mention of eggs. Charlotte spun in her chair, anger on her face.

‘It’s true,’ she said. She swung back towards us. ‘Isn’t it, sir? I’m right, aren’t I, sir? Tell them.’

‘Indeed you are, Charlotte. Perfectly correct.’ The teacher moved in front of us and clasped his hands together. ‘I imagine the laughter came from the mention of eggs. Hard-boiled, fried, scrambled, yes? Delicious on toast. But Charlotte is, as always, right. We all came from eggs, children. But this doesn’t make us chickens, does it? Do anyone of us really feel the urge to do this?’

He crouched down, knuckles on each hand touching, elbows wide. He strutted in front of the class, elbows pumping, head jerking backwards and forwards, clucking and clucking. The class groaned at first but then laughed harder and harder as he turned in front of them. I felt a smile on my lips. This teacher was either going to be the best or really annoying. It was early days so I only smiled.