“We didn’t set out to be obnoxious consuming yuppies,” said Kevin Salwen, as he opened the discussion of the book he wrote with his daughter, Hannah, The Power of Half at a New York City bookstore one snowy night in February. The room was filled with people who had come to hear about how Salwen and his family decided to sell their Atlanta mansion, move to a home half the size, and donate half the sales price – about $800,000 – to The Hunger Project to help villagers in Ghana.

It all began with Hannah, then 14, who had one of those moments that aren’t easy to shake. Father and daughter had stopped their car at a traffic light in Atlanta and were sandwiched between a homeless man with a cardboard sign and a man driving a Mercedes. That night Hannah became consumed with the inequities between the Mercedes driving man and his homeless counterpart and started nudging the rest of the family to think about doing something about that kind of inequity.

The something they decided to do – and the process the Salwen family used to get there – is the subject of a book that will likely become required reading for those interested in philanthropy, as well as those interested in life with teenagers. I had the privilege of working with Salwen around the time he was wrapping up the writing of this book. And it’s been a treat for me to watch as the book garnered the attention it deserves. Below is an excerpt from a recent email chat he and I had about the book:

Q: You are asking others to think about making similar changes in their own lives. You’re clear that not everyone has a 6,500-square-foot home they want to sell, but you ask them to think about what they can do within their own lives. What do you say to those who tell you they can barely take care of themselves and their families, let alone manage to give half of anything to others?

A: I’ll answer that in two ways: First, people who are struggling can find such joy and community in giving that it can help make their problems seem more manageable. Everyone has something to give, especially just a little time in their busy and difficult lives. If you build a project based on the road map Hannah describes in the book, you can make yourself feel better and more integral into the community at a time when you might be feeling little but stress and loneliness.

Second, and conversely, it may just not be the right time for those in the most dire straits. There are times in all our lives when we have more to give than at other times. And no, we don’t expect anyone else to sell their houses, but each of us can ask: Do I have more than enough of something in my life that could be of use to someone else? Time watching TV or surfing the web? Clothing that no longer fits? An ability to give someone hurting a hug? We’re betting the answer is “yes” almost all the time.

Q: Research tells us that it feels good and even boosts happiness to help others. And your book illustrates that. You travel with McDonald’s gift cards in the car glove compartment to give to the homeless; family dinners at the diner turn into a game of how to figure out where to do charitable work; Hannah springs out of bed, jazzed about working with you on a Habitat for Humanity house. How can parents create an environment that makes giving and philanthropy both natural and fun?

A: It’s funny, in our world we’ve created a belief that consuming is fun – let’s go shopping! – and service is work. But service is community and it gives us a much deeper and sustainable level of happiness. So, a few thoughts: Make sure you are finding the right service fit; it can be debilitating to work in service tasks you don’t enjoy. For instance, I used to tutor kids in English. I was a writer so I was “supposed to,” right? But I couldn’t stand the pace of progress. It was way too glacial for me. It wasn’t until I discovered the instant gratification of building a Habitat (for Humanity) house (and, by the way, I don’t have much in the way of construction skills) that I learned to love community work.

In our family, we never force someone to go along to a project they don’t love to do. For instance, when we serve dinner to homeless men at the Central Night Shelter, Joseph often doesn’t go; it’s “not his thing.” But he loves working at the Food Bank and eagerly signs up for that. And at the end of each service event, we always go out for a fun dinner or treat; it gives us time to talk over what we just did and increases our relationship time.

Q: What kinds of creative things have others done as a result of reading The Power of Half?

A: We know of a family buying a house less than half the size they had been looking for. (Came as a shock to their realtor!) We know of a girl in New York who, the night she heard us speak, went home and cleaned out her closets to send clothing to Haiti. We know of several of Hannah’s friends who are using half their babysitting money for charitable causes. We know of a CBS News producer who called the network’s story about us “the most expensive story I ever did because my wife immediately asked, ‘What do we have more than enough of?'”