Read some Piaget please!@prof_curiosity1
Girl Guides and the Single Sex Question: What Child Development and Safeguarding Tell Us
(longish post)
Girl Guides exists as a single sex organisation for a reason grounded not in prejudice but in developmental science. The research on adolescent girls consistently shows that dedicated single sex environments support confidence, risk taking, and identity formation in ways that mixed environments do not, particularly during the years when girls are navigating the social pressures of puberty and early adolescence. Removing the single sex character of those spaces does not leave them neutral. It changes them in ways that the developmental evidence suggests are meaningful.
The safeguarding concern is straightforward and does not require any claim about the intentions of individual children. Safeguarding frameworks are designed to manage risk at a population level, not to make judgements about individuals. Single sex overnight environments, changing facilities, and residential trips carry specific safeguarding protocols that depend on the single sex character of the group. When a child who is biologically male is included in those environments on the basis of a self reported gender identity, those protocols are compromised in ways that any competent safeguarding review would flag. The 2025 UK Supreme Court ruling, which confirmed that woman and sex in the Equality Act refer to biological sex, reinforces the legal basis for maintaining those boundaries.
The developmental harm to girls at this stage of their lives is not incidental. It goes to the heart of what single sex provision is for. Adolescence is the period in which girls are forming their understanding of themselves as female, navigating the physical changes of puberty, developing the capacity for intimacy and trust with peers of the same sex, and beginning to construct the adult identity that Erikson describes as the central developmental task of this life stage. The research on single sex environments consistently finds that girls in those settings show greater willingness to take intellectual and social risks, report higher levels of comfort with their own developing bodies, and demonstrate stronger peer relationships built on the specific solidarity of shared female experience. Those benefits depend on the space actually being what it presents itself as being.
When a biologically male child is present in that space, the girls in it are placed in a position that the developmental literature does not support and that safeguarding guidance does not anticipate. They are asked to manage the presence of a biological male in changing rooms, on overnight trips, and in the intimate social environment of a group that exists precisely to give them respite from mixed sex social pressure. They are asked to do this at the developmental moment when bodily privacy, peer trust, and the consolidation of a female identity are most significant. And they are asked to do it without their consent having been sought, and frequently without their parents having been informed. The schema formation argument drawn from Bem's work is relevant here: girls at this stage are actively constructing their understanding of what it means to be female, and an environment that systematically blurs the boundary between female and male does not loosen those schemas in a liberating way. It introduces confusion into a developmental process that requires clarity and safety to proceed well.
There is also a relational dimension that deserves attention. Bowlby and Fonagy establish that the capacity for secure peer attachment depends on environments that are predictable, boundaried, and safe. An environment in which the boundaries of membership are uncertain, in which girls may not know whether a peer is biologically male or female, and in which raising a concern is socially costly, is not an environment that supports secure attachment or genuine peer intimacy. The harm is not dramatic or visible. It is the quieter harm of a developmental environment that has been subtly but significantly altered at a moment when its character matters most.
The developmental concern for the boys themselves is less often discussed and deserves equal attention. Erikson and Marcia show that identity formation is a developmental achievement of adolescence requiring a genuine period of exploration and moratorium. A boy who is socially affirmed in a cross sex identity from an early age, placed in environments that reinforce that identity, and supported by institutional structures that treat the identity as settled, is a child whose developmental moratorium has been foreclosed before it properly began. The desistance literature, reporting resolution rates of sixty to ninety percent in pre-affirmation era cohorts depending on cohort and methodology, suggests that the majority of children expressing cross sex identification would, given time and space, arrive at a different understanding of themselves. Institutional social affirmation in single sex spaces of the other sex is not a neutral accommodation. It is an active intervention in a developmental process that the evidence suggests should not be foreclosed.
There is also the Winnicottian dimension, and it deserves more than a passing reference. Winnicott's account of the False Self describes a developmental pattern in which a child, faced with an environment that makes belonging conditional on performing a particular identity, learns to present that identity fluently and consistently. The performance does not feel like performance. It feels entirely authentic, because the child has no access to the True Self that the compliance dynamic has suppressed. The False Self is not a mask the child knowingly wears. It is a structure the child has built in order to survive an environment that could not tolerate what lay beneath.
The boy who joins Girl Guides as a girl is in precisely that environment. His belonging is conditional. It depends on the sustained presentation of a "female identity", affirmed by the institution, reinforced by every interaction within it, and socially costly to question or relinquish. The longer that environment persists, and the more significant the attachments formed within it, the more firmly the False Self structure is consolidated. The child is not being helped to discover who he is. He is being helped to become more fluent in a presentation that the institution requires.
What makes this particularly serious from a developmental perspective is that the harm is invisible from the outside and unfelt from the inside, at least while the compliance dynamic holds. The boy will report that he is comfortable, that he belongs, that the identity is real. That is exactly what Winnicott's model predicts. The False Self is a successful adaptation. It works. The cost is paid later, when the True Self, having been suppressed through the years in which identity formation should have been occurring, eventually reasserts itself, often in the form of the acute distress that characterises detransition accounts. Those accounts, which describe not simply a change of mind but a profound sense of having been absent from one's own development, map with considerable precision onto the clinical picture Winnicott describes.
None of this requires hostility toward any individual child. The appropriate response to a boy experiencing gender related distress is compassionate, thorough clinical assessment, careful attention to the possibility of underlying anxiety, attachment difficulties, or social factors, and the kind of watchful, patient support that allows development to proceed at its own pace.
Placing that child in a single sex environment organised around an affirmed female identity does not provide that support. It provides the conditions in which a False Self consolidates, development forecloses, and the reckoning is deferred to a point when it will be considerably harder to bear.