Wanda the Witch, accompanied by Harry the Horror, flashes onto the screen in bold uniform colours as carnival music plays on repeat. They have captured Marvin and, using our math skills, we must rescue him. There is a sense of urgency to this. A wrong number is clicked, a flash of orange fills the page, and Marvin crumbles.

This is not the outcome we are supposed to want, yet we huddle around the computer cheering. The defeats, in Math Circus, are better than the successes. When the correct answers are clicked Harry morphs into a frog and Marvin is freed, an acrobat swings across the screen. When the wrong answer is chosen clowns are drenched in technicolor paint, the acrobat falls to his demise.

Wrong answers could be justified in the computer lab, more so than in real life. We had two options, we could pretend our mistakes were a result of computer error, or we could take a sadistic streak and revel in the character’s failure. I did that on purpose. Tricked into math through the allure of being allowed to use the computer, we spent the allotted hour in a trial and error bliss.

The witch raises her wand.

She turns Harry into a frog.