Carole ~ I had a couple of other ideas.
How about a bake sale or a car wash?

Do you know of any kids in Girl Scouts or Boy Scouts? (Are they called Girl Guides, in NZ?) When I was a kid, my Girl Scout troop adopted a shelter as a cause and we raised money (and earned badges) for them.

In the US, most of us have jars and jars full of pennies because they are basically worthless and you sure can't buy anything for one cent anymore. So, we once went door to door (with flyers for the shelter) and collected as many pennies as we could. We got several hundreds of dollars that way. Does NZ have a similar coin? One everyone has a bunch of hanging around the house.

Good luck and keep us posted.

Lisa