Book cover for The Irrational Diary of Clara Valentine by Coralie Colmez, compulsory maths, rishi sunak


WINNER Chalkdust Magazine Book of the Year 2022!!

Free PDF here or spend your money 'cause the book is pretty:

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Clara's last year at school is looking pretty uneventful, apart from the stress of uni applications. Until one day, classmate Ty (on whom she happens to have a pretty big crush) asks for her help. His computer genius brother has just disappeared, leaving behind a laptop to which access is granted only when you answer a maths question - and maths isn't exactly Ty's strong suit.

One question turns into many when Clara and Ty follow his brother's trail and start spending a whole lot of time together. As she works on maths problems more exciting that anything she's ever done in class, Clara also has to deal with everyone in her life suddenly acting strange all at the same time: best friend M's gone silent on her, little sister Emma has become a devil child, and even her parents are up to something...

This book is self-published. There were a few interested publishers, but they all thought I should cut out the maths, or the sex scenes, or make the mystery bigger, or smaller... basically, they wanted me to make it obvious 'which bookshelf the book would go on in a shop'. But my own life involves a bit of everything - maybe no disappeared genius computer hackers, but definitely work and love, maths and sex, politics and philosophy and TV shows, and yes, even some mysteries. I really wanted Clara's life to look like that too, so I hope you enjoy this many-bookshelves version!  And reading it will make you super smart as you'll get to tackle some beautiful, famous maths problems along with Clara, from code-breaking to number theory and logic.


This non-fiction book describes ten trials spanning two centuries and several countries, in which mathematical evidence was used – or rather, disastrously misused – as evidence.

Among others, you’ll read the stories of Sally Clark, who was accused of murdering her children by a doctor with a bad understanding of probabilities, of nineteenth-century tycoon Hetty Green, whose dispute over her aunt's will became a signal case in the forensic use of mathematics, and of Dutch nurse Lucia de Berk, falsely accused of having murdered her patients with the help of some faulty data collection and erroneous calculations.

Book cover Math on Trial by Leila Schneps and Coralie Colmez

I wrote this book with my mum back in 2010! It has been used as a textbook for uni, and by students doing their EPQs, which is definitely the coolest thing that's happened in my life. It's also brought me some amazing opportunities like giving talks to hundreds of students and teachers about maths.