I think the best way to educate your children about philanthropy is by example. Both of my parents came from humble beginnings, but they were raised to believe in "being of service." That manifested itself in many ways during my childhood, one of the most important ways was that they both volunteered their time to charities. I remember my mother telling me how important it was for older people to feel connected to their communities, so I would help her do arts and crafts at the nursing home near our house. I also remember her volunteering to work at the polls on Election Day. This was really interesting to me as a kid because I got to see how our democracy works up close rather than just reading about it in a book.
When you're not sure what kind of work will inspire your child, try different kinds of charitable activities until you find one that your kid can connect with. I plan to take my daughter on my trips when she is old enough. Seeing how other people live around the world is very eye opening at any age! But even going down to your local homeless shelter and serving food for Thanksgiving is a powerful reminder to all of us, young and old, of how much we have to be grateful for, and how much we have to give. The kids may complain a little bit, but I believe that the memories and impressions provided by the experience will help to shape who they become.
Whenever I am at The David Sheldrick Wildlife Trust nursery I am reminded how much children love animals. There are always lots of little children there visiting their adopted elephants. The children and the elephants seem to relate to each other with a special language. Each child knows the story of how his or her elephant was orphaned and each child wants to be a part of taking care if that little "ele." Children are naturally generous, and "adopting" an elephant gives them an education in so many things like science and our environment, through the updates that come every month focus on the growth and development of that "ele." It's so beautiful to see each child relate to another animal in this way. I highly recommend adopting from the Trust for your little one.