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...

Praise for The Irrational Diary of Clara Valentine:

"I had no idea you were this funny!" Coralie's mother, a mathematician

"Coralie's voice is so effervescent, so authentic, so engaging [...] I think she's a star in the making" A publisher who didn't publish the book

"Super exciting and relatable" Coralie's sister, a real-life teenager