Editor’s Note: When I met Estrella Rosenberg April 8 at the Nonprofit Technology Conference, she told me about the Foursquare 100×100 campaign to launch two days later. No one had used Foursquare in this way previously, and I immediately knew she was on to a breakthrough idea. I asked her to send me a writeup once it was over, and this is her guest post below.

When April 1st rolled around I had been investigating how non-profits use Foursquare and brainstorming how they could  use it for a couple of months. Although not a direct method of fundraising my thoughts were still along those lines…and then a question popped into my head. Could Foursquare be used for awareness and advocacy?

1 in 100 children are born with a heart defect. My two nonprofits Big Love Little Hearts and One Hundred Squared serve the Congenital Heart Defect (CHD) community. When was the 100th day of the year? It happened to be nine days later, April 10th. My next question was: “could I come up with a campaign in nine days, launch it and have it be successful?”  I had no idea but I’m not afraid of failure so I set out to create a Foursquare experiment.

The basic premise was this – we created a hashtag, #100X100, that stood for 1 in 100 on the 100th day of the year. I created a website, http://onehundredsquared.com to explain what it was, why it was important and to determine the actions we wanted supporters to take: spread awareness using the hashtag and call/write their representatives asking them to support the Congenital Heart Futures Act and Pulse-Ox screening of CHD to the National Newborn Screening Panel. We also created a Facebook fanpage and Twitter profile.

We recruited volunteers to commit to a guerrilla, grass-roots effort to use Foursquare to parlay our message. On the evening of April 9th a few dozen Big Love Little Hearts volunteers added the following as a “tip” to 600 Foursquare locations:  “1in100 children are born w/ a heart defect. Pulse-Ox screening saves lives – you can too! Check in with the hashtag #100X100.” We also embedded a link in the tip to the One Hundred Squared website. We chose what we thought would be the most checked-in locations on a Saturday: airports, Starbucks’, Target’s, gym’s, etc. in every major city.

One of the benefits of using Foursquare as an origin point is that most people who use it sync their check-ins to Twitter and Facebook. This meant that one person checking with #100X100 had the possibility of being viewed across three different platforms with three audiences. Talk about bang for your (time) buck!

Did it work? Better than I could have possibly imagined.  My goal was to see how social media worked for advocacy and awareness. However, something extraordinary happened: I began foursquaring/tweeting/facebooking about #100X100 at 12:01 am on April 10 and Big Love Little Hearts’ supporters followed.

At 7:30 am an angel who was following one of our followers on Twitter (but not us) noticed our hashtag. (She is an adult with a CHD who was not diagnosed at birth and who is alive today because she received lifesaving surgery.) Her passion for our work led her to call me and commit to donating $1 for every time someone used the #100X100 hashtag until midnight April 10th.

How much did we raise?  She gave me a cap of $25,000. I knew the moment she said it that as a not-quite ten month old organization we wouldn’t reach the cap. Much to my surprise our supporters were so engaged that we reached it by almost half.

At quarter to midnight the hashtag had been used 11,703 times across all three platforms. Our donor was so impressed that she committed all $25,000, which funded 12 surgeries in developing countries. Twelve lives saved in 24 hours.

That’s great (okay, FANTASTIC), but did it work for advocacy and awareness? YES! Less than two weeks after the 100th day of the year about 100 people from various CHD groups were to meet in Washington  for CHD Lobby Day. The One Hundred Squared website, as linked through Foursquare and the hashtag, asked people to contact their representatives. We wanted to plant a seed for anyone who used #100X100 on the 10th to call their Senator or Congressman and let them know that they supported measures that would greatly improve the lives of the 2 million people living with CHD in the states.

On the April 22 (CHD Lobby Day) we used the hashtag via Twitter, Facebook and Foursquare to remind our supporters to call their legislators. By noon more people had looked at the website than the entirety of April 10. I had seven appointments with Senators  & Congressman from Illinois that day. There wasn’t a single one I walked into where their aide didn’t inform me that constituents had been calling about this all day. People Lobby Day delegates from other states texted or called me to say the same. More than 500 people told me that they had contacted their representative, and 300 others contacted the Big Love office to do the same. 1800+ viewed the page and clicked through the link to find their representative. I cried with pride the entire day.

What was the benefit of using Foursquare as our social-media springboard? The tips we left are still there and will stay there perpetually. For several locations our tip is still the most recent. Did I mention that we have a link embedded in the tip?

A huge “thank you” to everyone who participated in #100X100 on April 10h and 22 – you made it such a success that the Big Love Little Hearts sister organization, 1 in 100, changed its name and expanded its mission. (Check back with http://onehundredsquared.com soon – or subscribe -for more details)!

One last nugget – all of this was FREE. We raised $25,000, saved 12 lives in the immediate and set the stage for millions of lives to be changed.

Estrella Rosenberg is the Founder and Director of Big Love Little Hearts, One Hundred Squared, Little Leo Foundation and The 4F Club. She writes about her love of non-profit work in her blog, Adventures In Philanthropy.

Big Love Little Hearts provides lifesaving surgery to children with congenital heart defects in developing countries. Almost one million children are born with a heart defect worldwide every year – half will need surgery to survive. Ninety percent will be born in countries where access to lifesaving measures is limited by economic status or lack of infrastructure. Follow them on Twitter. Follow One Hundred Squared on Twitter here.