Look, we can't pretend that teaching empathy is easy, or that any of these approaches have worked perfectly. I'd love to say that after seeing impoverished kids in Cambodia who were desperately eager to go to school, our own kids suddenly came to see school as an opportunity rather than a burden. Not true: They still don't bound out of bed on school days with smiles on their faces. But the cumulative effect of an exposure to the needy at home and abroad, coupled with encouragement to engage in efforts to make a difference, has had some impact on their thinking and behavior.
One of the things that parents learn is that children never turn out exactly as we intend: There's no magic formula for childrearing. But modeling empathy does make a difference, and it's one more reason why we ourselves are often the greatest beneficiaries when we reach out and try to help the neediest around the world.