Every day is Earth Day in our house.

It's not just because I brought my kids out of the country that has the fourth-largest impact on global warming and moved them to the country that is the biggest culprit. Taking care of the Earth simply makes sense because it is our one and only planet. And since my kids, by virtue of their adoption, are already global citizens, I'm hoping they can be in the vanguard of the global citizens trying to turn the world's pollution problems around.

I have tried to teach my kids what we should and shouldn't be doing to it from the very beginning. My kids know it's lights out when they leave a room, and TV off when they are done with their shows. They vie for turns to turn the drip hoses in the garden on and off. They have already decided whose turn it will be to put in a compact fluorescent when the next incandescent bulb burns out in our house. They know how to separate table scraps for the composter. They know we walk to school except in cases of blizzards and monsoons.

And they have really taken it to heart: My little guy was pushing a toy replica of a gas-powered lawn mower around the other day and said with a wink, "look Mom, I'm polluting." (We have a human-powered reel mower.) When McDonald's gave out toy Hummers with its Happy Meals last summer, my older son remarked that it was probably going to be the only Hummer near our house. (We drive a hybrid.)

But when my older son began planning what we could do for Earth Day this year, he ran into a problem: It's getting pretty hard to cut our carbon footprint. He first suggested we buy solar Christmas lights so we could have an outdoor display this year, but we couldn't find any. (Memo to the Christmas decoration folks: Please work on this for December.).

After much back and forth, we came up with two new commitments: walk to church and dry clothes outdoors. I can tell you that latter one is going to be hard to stick with, but good ideas often are.