One day at school, we were asked what we wanted to be when we grew up. Andrew said that I should be a scientist. Scientist wear glasses and I wear glasses, so he said that that is what I should be.

If I was going to be a scientist, then I was going to have to invent things and stuff like that. I would need a laboratory to work in and chemicals to work with. In our house, there was only one place to do that: the medicine cupboard. In there, I could find all sorts of strange chemicals to make potions with. I could mix up secret formulas in the cupboard where no one could see me. I could try them out on my brother Frank; he could drink my potions and then I could watch and see what happened to him.

Frank and I went into the bathroom, opened the medicine cupboard, and went inside. We turned the cupboard light on, shut the door, and climbed onto the top shelf. I had brought one of Mum’s teacups to mix things up in.

On the top shelf, there were all sorts of chemicals, and some of them had labels. Quite a few were in green and brown bottles, and some had ribbed glass so you could feel it in the dark and know that it was a chemical. Most of the labels were old and faded and were difficult to read. They had strange names like “potassium permanganate” and “magnesium sulphate,” or they had names that told you what they did, like “wart remover,” “cough syrup,” or “head lice shampoo.” There were quite a lot of other things too, like bubble bath and cologne. I counted them all and there were over a hundred different bottles and packets.

Frank and I set to work mixing things up in the teacup. We started with some nice bubble bath that looked sort of shiny and we thought it looked a bit like a secret formula to begin with. Then we started to add all sorts of things. We knew it would be ready when it started to bubble up and smoke, but no matter how many things we added to the bubble bath, it never started to bubble or smoke. Instead, the potion turned a sort of murky brown, like old tea with milk in it.

We added all of the chemicals and that seemed like the best it was going to get. I handed the teacup with the potion to Frank for him to drink, but he shook his head and said no thanks and that he didn’t want to drink it. Well, what was the point of having a henchman if they won’t do what you tell them to? Frank said that he wasn’t a henchman and that he wanted to be a scientist too.

While we were arguing, Dad came up to use the bathroom, and when he saw the teacup with brown milky liquid, he started to complain about how hard he worked to make enough money to buy tea and milk and how it was a terrible waste to let our tea get cold and not drink it. Whose tea is it, he asked.

Frank said that it was mine, and Dad insisted that I drink it all up, every last drop; it tasted horrible. Once Dad was gone, I ran back into the cupboard, and there I underwent an astonishing transformation. I could feel bits of me growing and bits of me shrinking. My hair grew longer and so did my nails, and when the transformation ended, I came out of the cupboard a beautiful girl. I had long hair tied in pleats and long fingernails that were red with nail polish. My clothes had changed, too: instead of wearing shorts and a shirt, I was wearing a pink satin ball gown with blue voile over it that made the dress sort of shimmer when I moved. It was a very beautiful dress.

Being a girl was great; girls are much better than boys. Girls get to do all sorts of things that boys don’t. They get to sew and cook with Mum, and they get to play with dolls. Boys carry their school bags for them, and some even do their homework for them. They get to dress up very pretty and have lots of clothes and makeup. Girls are much prettier too. When was the last time you heard someone say “Who’s a pretty boy then?” and they weren’t taking about a parrot or a budgerigar? My experiment had been a great success.

Dad was not very happy. He was worried about what the school would say, but Mum said to tell them that I was Robbie’s cousin come for a visit and that I had gone to visit my aunt in exchange. I didn’t have a cousin, but I thought that would work. Mum was happy because it meant there was another girl to help with the housework and cooking and stuff, and now that I wasn’t a boy, I would not be going out and getting dirty and tearing my clothes climbing trees and playing football.

They decided to call me Robbietta. We had to come up with a girl’s name really quickly and that was the best they could come up with.

Obviously, I couldn’t wear a pink satin ball gown to school, so I had to change into some of my big sisters’ old school uniforms and then head off.

School went very well. Allan, who was the biggest boy in the class and always tried to bully me, gave me a wolf whistle when I walked past. In the class, when Mrs. Crown asked a question and I put my hand up, she never said “that’s enough from you, Robbie, let someone else have a chance,” but instead said “let’s hear from the new girl, shall we?” In the lunch queue, I didn’t have to push and fight for a place with the boys; instead, some of the girls in my class, Laura and Gillian, shouted me over to join the queue with them. It was much nicer and I liked spending time with Laura and Gillian. Gillian wasn’t my girlfriend, but I did carry her school bag for her and once we made papier-mâché Easter eggs at school and I gave her mine to keep and she said thank you and that it was very nice, even though it wasn’t, really.

Later, my friend Andrew carried my school bag for me. He didn’t know it was me.  He said “I’m your cousin Robbie’s best friend, so let me look after you for him.” I thought that was nice. He never carried my school bag when I was just Robbie. When we walked home, he talked very seriously and I said nothing and pretended to be shy. I knew that Andrew liked girls that don’t talk very much and are shy.

The new arrangement seemed to suit everyone, except for poor Frank, who didn’t have a big brother to stop all the big boys bullying him. If I had still been his big brother and not his cousin or big sister or whatever I was, I would have put a stop to the other kids teasing him pretty quick, I can tell you. But what is a girl to do? She must always act ladylike. I told Andrew about the problem—or some parts of the problem—when we went home and he was carrying my school bag. He told me not to worry my pretty little head about it and that he would take care of it.

I was a bit worried because Andrew is very clever, but not a very good fighter. The next day at school, at lunch time, Andrew and Allan got into a fight. Allan is much bigger than Andrew and was winning easily. Well, girl or no girl, I couldn’t let Andrew get beat up for me. So I took my school bag and started to bash Allan with it until he let Andrew go.  Both of them had to go and speak to the headmaster, and so did I.

We all stood in the headmaster’s office while he told the boys how disappointed he was in their behaviour and that he expected better of them. He gave both of the boys a hundred lines to write out “I must not fight in school,” and then he told me that I had been very brave and that he hoped that I had not found things too upsetting. I said no and then we all went back to class.

On the way home, I told Andrew how thankful I was and how brave he had been. At the gate of our house, he handed me my school bag and then he did something very odd. He leant forward and kissed me, right on the lips. I had never kissed a girl, or a boy for that matter, and I’m pretty sure that Andrew had never kissed a girl either.

I’m not sure how I felt about Andrew kissing me. It wasn’t horrible or anything, just odd. I’m sure people can get used to kissing. I read in a book that French people kiss all the time. But it was very confusing.

That night, something else strange happened. When I woke up the next morning, the potion had worn off, and I had turned back into a boy. I put on my boys’ school uniform and went downstairs. I expected everyone to be annoyed that I had turned back into a boy, but they were mostly quite happy about it except for Dad, who complained that he’d wasted lots of money buying me girls’ clothes and now he would have to get me boys’ clothes instead.

I told Mum how sorry I was now there would be fewer people to help her with sewing and cooking and stuff. But she said that it was fine: it had been nice to have Robbietta visit for a while, and she had enjoyed their time together, but it was nice to have Robbie back too, and that she’d missed him a little bit. She said that she would love me if I was a boy or a girl; it made no difference to her. Frank asked me if I would turn back into a girl, but I said I’m not sure. I forgot to write down our secret formula for turning boys into girls.

At school, I met Andrew.

“You’re back,” he said.

“Yes,” I replied. And I asked him how he liked my cousin Robbietta.

“Not much,” he told me; he said that she talked too much and was very bossy. He said that she had made him carry her school bag for her and had gotten him into trouble with the headmaster.

“Did you think she was pretty?” I asked.

Andrew shrugged. “I suppose so,” he said.

When we got to school, Gillian sat beside me in class. We made pictures using bits of coloured paper that had glue on the back. I licked all of the glue on the back of the coloured paper so Gillian wouldn’t get a dry mouth, and when we were finished, I gave her my picture, which was of a vase with flowers, to keep. Gillian said thank you and that it was very nice, even though it wasn’t. Later, I carried her school bag all the way to her house. I decided that being a boy wasn’t all bad. But I was going to try and rediscover my secret formula for turning into a girl, just in case I changed my mind.