You matter on Earth Day:

On April 22, 1970, 20 million people across America celebrated the first Earth Day. It was a time when cities were buried under their own smog and polluted rivers caught fire. Now Earth Day is celebrated annually around the globe. Through the combined efforts of the U.S. government, grassroots organizations, and citizens like you, what started as a day of national environmental recognition has evolved into a worldwide campaign to protect our global environment.

Here are some ideas for small changes you can make:

Put on your thinking cap: Top 30 Earth Day ads.

Does Earth Day matter? Jim Motavalli finds it's best as a decentralized, local event.

One day only! Save a buck (and paper, too!) with this free coupon application for iPhones.

Playing in the dirt with Arthur: PBS character helps kids learn about gardening this week.

Make a plan: Use this tool to find out what's happening in your area for the big day.

Hit play: Chuck Leavell of the Rolling Stones shares his favorite eco-friendly songs.

What's your Re:Solution? Employees at The Gap do their part for Earth Week.

Reading list: Peter Dykstra's favorite environmentally themed books.

And something for kids: "The Barefoot Book of Earth Tales"

Eat right for Earth Day: Did you know it's also Low Carbon Diet Day?

The real cost of driving: This new widget will open your eyes on gas costs and CO2 emissions.

The Disney view: Mickey Mouse dips a toe into the nature documentary genre with a big-screen debut.

Earth Minute? Now there's a cause our fast-paced world can support!

Underwater explorer: An easy device to help your kids see what's under water.

Eat sustainably: 10 things you can do to change your own eating habits.

Dine out for the earth: New York City's il Buco offers a great deal and a great meal.

Laugh every day: Paul Rudd rocks Sesame Street.

Earth Day on TV: We've mapped out your TV plans with Martha Stewart, Cameron Diaz and Drew Barrymore.

Laugh and learn: How to have an extreme Earth Day.

Small steps: 10 things you can do to make every day Earth Day.

Help kids go green: New book uses illustration, simple language to help kids think green.

Earth Day concert! Watch Ben Harper perform live at Piazza del Popolo in Rome on Nat Geo Music.

Don't blow it: Plant a tree to curb your allergies.

Red, red wine: Raise a glass to Mother Nature, an increase awareness while you're at it.

Real reality TV: Get ready for a new definition of reality TV in advance of Earth Day.

360 Cities: Get immersed in nature with interactive photographer's paradise.

Green building summit: BrightTalk to host a day of green building webinars.

Take your best shot: The EPA wants to see your best eco-inspired photograph.

Tweet away: And win great prizes for Earth Day!

Bringing joy with soy: Aveda's eco-friendly candle will raise money for clean projects around the world.

Loud and proud: Let your neighbors know you're green with this flag.

Green jobs: Flexjobs will donate a tree for every new subscription this month.

Now, go make a difference!

Here's what you can do to improve the earth:

• Earth Day at home

• Earth Day at the office

• Earth Day at school

• Earth Day in your community

Helpful information:

Learn more: EPA has made progress since the 1970s. Here are the details.

Tease photo: Zemdega/iStock

Earth Day ideas
On April 22, 1970, 20 million people across America celebrated the first Earth Day. It was a time when cities were buried under their own smog and polluted rive