Last Saturday night, my children wanted to turn off the lights and go to bed early. “Hurry up, Mom,” they urged, reminding me to read their bedtime story faster so they could turn out the lights by 8 p.m.

What was even more unusual about this singular event was that they were doing it to save the planet.

Even though Earth Hour isn’t until next Saturday, the girls wanted to practice. They don’t get a chance to be part of a global movement very often, and they wanted to get it right.

This particular effort — Earth Hour — started last year in Sydney, Australia. At 7:30 p.m. on March 31, 2007 more than 2 million people, more than 2,000 businesses, decided that they would do something to show that global warming isn’t a hopeless cause. They turned off their lights.

The lights were dark for only one hour, but during that time, Sydney’s demand for electricity was reduced by 10 percent. This result far exceeded the organizers’ 5 percent goal of energy reduction and inspired them to take the effort worldwide.

This year it is our turn. On Saturday, March 29, cities, businesses, churches, schools and homes across the globe will go dark from 8 p.m. to 9 p.m. Lights will dim in Atlanta, Bangkok, Charlotte, Chicago, Dublin, Phoenix, San Francisco, Tel Aviv and Toronto, and many other cities all over the globe. And even though Cary isn’t on that list, we can still participate.

Earth Hour is a chance for us to take that first, or second, or 100th step toward fighting climate change. It’s easy. No commitments. No big investments. You don’t even have to use public transportation. At 8 p.m Saturday, March 29, turn off your lights, television, computer, stereo, microwave. Light a candle. Spend an hour talking with friends or family.

It won’t be that bad, really. At 9 p.m. turn everything back on. Then sit back and feel proud of being part of a truly global movement. I believe that this pride, this global togetherness has captured the imaginations of my children.

The environmental problems we face are so big. I can’t imagine how immense they must seem to a child. But this is something they can do.

They can switch off their lights. And they can go to the Internet and see lots of other people switching off their lights. They will be able to see tangible results of millions of people acting together.

Now will this one night, this one hour, make a dent in the huge problem of global warming? Probably not. But what this one night, this one hour does show is what humans can accomplish. By working together, we can do great things, we can make a difference. That’s pretty exciting stuff — even if you’re not a kid.

Turn off your lights, join a global environmental movement.