Girl Maths: The Plusses and Minuses

by Tanja Cilia

When I worked in a school, I never threw away children’s glue sticks when they were “finished”. I’d scoop out the leftovers from several tubes, press them together and, as if by magic, produce a brand-new glue stick or four. It was satisfying, reduced waste and, if I may say so myself, was rather clever.

A friend once described Girl Maths in much the same spirit. “I have to buy five lipsticks,” she insisted, “because five nearly empty lipsticks become one free lipstick.” It sounds like the sort of shopping logic that has fuelled countless memes, yet the underlying idea is perfectly sensible. She wasn’t really talking about buying more make-up. She was talking about making the most of what she already had. The conclusion sounds like a hackneyed shopping justification, albeit the action is genuinely sensible.

That, perhaps, is why Girl Maths has proved so irresistible. Strip away the pink packaging and the TikTok punchlines, and much of it is simply Lateral Thinking applied to everyday spending. It is a playful way of looking at money, which often contains a grain of practical wisdom, albeit if it arrives dressed as a joke.