Institutional Gender Discrimination - Science Museum

Gender Discimination - Science Museum, London
I have shared residence ordered by consent. My daughter stays with me every other weekend and half the school holidays. As a treat, I planned to take her and a few of her girl friends on a special weekend - an overnight science extravaganza at the Science Museum in London. The Science Museum offers sleepover events for children aged 8 to 11. However, I am banned from doing this for my daughter because of the 'Science Museum's rules for accompanying adults'.

Here is the relevant section of this publicly funded body's rules:

'How many adults do we need?'
 * 1) For an all girl group you will need 1 female adult for every 5-6 children
 * 2) For an all boy group you will need 1 female or 1 male adult for every 5-6 children
 * 3) For a mixed sex group you will need 2 female adults or 1 female and 1 male adult for every 5-9 children

Here is the link to the Science Museum's website:

As my daughter does not have any boys as close friends, I am constrained by the facts of her social life to take a group of girls which I am now not able to take because a father is not allowed to look after his daughter and her girl friends (even if the girls' parents are fine with this). Thus decrees an organisation funded by tax payers' money.