Here's a cool blog written by a 6th grade girl called "25 Days to Make A Difference". For the first 25 days of each month, she works on a charitable project; she tells you the project at the beginning of the month, reports on her progress, and then tells you how it went! One month it was collecting books for her library's book sale and collection. Another month it was turning in glass bottles and aluminum cans and using the collected deposits to help animal charities. It's really interesting and she has a fun time choosing projects! Each month she also makes a donation to the favorite charity of one of her commenters.
You can read more about her projects at http://twentyfivedays.wordpress.com.