Watch out if you get the wrong muffin; you might be categorized as your biological sex.

It sounds ridiculous, but it’s true: as part of the “mixed-muffin gender berry challenge,” roughly 1,400 young Welsh people participated in an exercise with muffins designed to make them feel what a transgender person feels. The challenge worked like this, according to The Times:

The exercise distributes muffins around a group. Those whose cakes have blueberries inside are asked to stand by blue balloons, representing the stereotype of masculinity in one corner of the room. Those with raspberry muffins are asked to stand by pink balloons, representing the stereotype of femininity, in another corner. Those with mixed muffins found that they had no place to stand.

The challenge is one of the exercises included in Agenda, a free online toolkit; the guide for the challenge stated:

After this activity, we asked how they felt being categorized according to a muffin they did not choose, what it felt like to go to a gender-coded corner that they might not identify with, and what it felt like not to have a corner at all. This got us all talking about how we come into the world already coded through gender labels; how you can’t assume someone’s gender by how they look: what it feels like to be given a gender you might not choose; and not to have your gender represented at all.

The author of the challenge, Emma Renold, professor of childhood studies at Cardiff University, was paid over $13,000 for her work including the Agenda guide. She is the author of “Girls, Boys and Junior Sexualities,” “Children, Sexuality and Sexualisation,” and “Young People and Gender & Sexuality Activism.” She chaired the Welsh Government’s expert panel on the Healthy Relationships Curriculum.

Kathleen Stock from the University of Sussex, said the “confused and contradictory” exercise “read a bit like satire,” adding, “The materials are troubling because they effectively encourage young people, and particularly gender non-conforming girls and young lesbians, to conclude that their distressing feelings aren’t just a sign that the world is sexist, but rather a sign that they themselves need fixing.”

Renold countered, “The aim of the muffin challenge was to explore how social and cultural gender norms shape and inform how school policies and practices categorize students using assumed sex/gender identities.”