I hate the idea of it being frozen. There have been times when I have depended on CB.
One of the best things about it is that it is given to the mother. This means a lot to me. I don't have to fight for it, I know I will spend it wisely, the government is in effect saying to me 'you are the best person to administer this'. Irritating for men, perhaps, but men still earn more on average than us, and it is like a tacit agreement that yes, society is unfair but we're trying to redress the balance.
In the situation you describe, Chil, tax credits won't be automatically given to the mother.
I think there is a place for universal benefits that are easy both to administer and to claim. Everything else is very complicated. Maybe linking it to earnings as expat says, but some of the richest people don't work!
Edam, the government could never see it as a 'reliable' source of income as we are talking about donations.
I suppose we are free to not claim it. But then the government could use it for something we don't agree with. If we donate it, we get to choose where it goes.
How hard is it anyway for the local council to set up a system for you to divert your CB into a fund that is to be used only for schools? It would be an interesting experiment, I think.