Petition Charity fundraising events allowed in all schools

There are so many charity fundraising events that take place all over the UK, including Red Nose Day, Christmas Jumper Day and general mufti-days all of which generate great amounts of money for charities.
Most schools take part in these and they are great fun as well as for a great cause. Not all schools do however such as my school. I am in year 13 and the head teacher has never allowed any events such as mufti day and Pink Day.
I think this is disgusting and all schools should provide the opportunity to take part and raise money for charity. 'Banning' these events is disrespectful and charity fundraising should be encouraged as opposed to discouraged.