MNN week in review montage

Our picks for the week of March 13-19: 

• There's nothing like a treehouse to make you feel like a kid again, and these 18 examples won't disappoint. Enjoy these stunning treetop structures and the unique stories behind them.

• The nation celebrated St. Patrick's Day this week. What could be more fitting than a introduction to seven American organic beers? Cheers!

• Many breathtaking caves can be found within rocky coastal cliffs. Here are nine extraordinary examples of water caves.

• You've already seen some gorgeous examples of Mother Nature's handiwork today. Here are seven apps to make the most of the great outdoors.

woman with pet in a shelter in Japan• The story we couldn't avert our eyes from this week was the disaster in Japan. From daily developments to analysis, it was hard to break away. We learned about the ups and downs of nuclear power and the resiliency of the Japanese people. Those not immediately affected wanted to know how they could help. Here are links to help shelter organizations, pet rescue groups and make simple online donations

• There are plenty of unbelievable stories out there that are true. (Case in point, above.) But a new survey shows that many people think science fiction is real.

• This week, we take you to Curitiba, Brazil, a city that boasts efficient public transportation, a vibrant organic scene and plenty of eco-conscious hotels.

• You'll want to look up at the sky on March 19 — just to say you've seen the supermoon. Don't know what that is? Here are five facts you need to know.

• Our business blogger is up in arms about the debit card cap debacle, the proposed limits on spending that could affect all of us. (What do you think?) 

PLUS: Don't miss the week in photos. Have a great week.

MNN week in review: Wondrous treehouses and breathtaking caves
Catch up on the environmental headlines from Mother Nature Network for the week of March 13-19, 2011.