It wasn't for charity but there is this little girl who is sick and wanted people to send her rainbows. My group and I made lots of rainbow pictures and mailed them to her. I will try to find the info on this and post it for you.

What about talking about food banks and how people go there for help. They could ask their parents to bring in food and you guys could deliver it?

Or Christmas presents for the less fortunate? You could wrap up a few gifts and deliver them to a church, women's shelter, mall?