In honor of Social Media Week, I asked a few of our favorite nonprofit experts to weigh in with their personal picks for nonprofits who are hitting it out of the park on social media. Here’s what they had to say:Mark RovnerPrincipal, Founder & CEO, Sea Change Strategies National Audubon SocietyWhere I follow them: Facebook and TwitterWhy they’re so awesome: Social media manager Elizabeth Sorrell knows her audience and feeds them a generous supply of bird photos, interactive challenges, and conservation news. She’s made the Facebook page incredibly fun and lively, and the extremely high level of engagement is testimony to that.Darian Rodriguez HeymanCo-Founder, Social Media for Nonprofitscharity:waterWhere I follow them: TwitterWhy they’re so awesome: Everyone talks about how amazing charity:water is at outreach, but one specific thing they’ve done on Twitter to get to over one million (!) followers is their “photo of the day” campaign. They use the assets they have incredibly well, and that’s the key to their success.Alia McKeePrincipal, Sea Change Strategies and founder, LifeboatAmnesty International Where I follow them: Facebook and Twitter Why they’re so awesome: They are timely, relevant, authentic. They use engagement data to optimize their social media communications. They use social media as a listening tool to tap into what their supporters are thinking and feeling about human rights. That info gets communicated to the fundraising and advocacy teams and informs integrated campaign opportunities. David HartsteinWired ImpactNo Kid Hungry Where I follow them: Twitter, Facebook, and Google+Why they’re so awesome: From the name of the organization to the information they share, No Kid Hungry does an awesome job of communicating their mission in a clear way. On social media, they vary the content they share to provide a wealth of value to those interested in ending childhood hunger in America. Despite their sizable following, they take the time to engage with individuals, responding and thanking supporters publicly. No Kid Hungry sets a great example for all types of organizations.Joe WatersSelfish Giving and author of Fundraising with BusinessesGeorge Washington’s Mount VernonWhere I follow them: Twitter and PinterestWhy they are awesome: They do a wonderful job creating unique content for their site and promoting it on social networks. For example, in October they really captured the macabre spirit of Halloween. They had a great post on people who had claimed to see Washington’s ghost through the years. Thanks to their activity on Twitter, I recently discovered a detailed post on how Mount Vernon looked when Washington lived there in the 18th century. Finally, Mount Vernon doesn’t restrict their content to text. They also have an active YouTube channel. Check out this video on Washington’s dentures! As a guy who follows and loves history, Mount Vernon really makes it come alive!Want to improve your organization’s social savvy? Download our free social media guide.