In this article we critique, disrupt and resist the taken for granted use of the term fun in learning; specifically as it is used to justify mathematics education apps that purport to portray maths learning as a fun experience. We accomplish this critique through the creation of a digital artwork called Arithmomania. This artwork challenges how users interact with education apps by employing the aesthetic of the glitch, an aesthetic characterized by reifying disorder and malfunction. Arithmomania shows fun as a miasma to learning, rather than the nostrum it is believed to be.