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Science Shared on Online Communities

Last spring, thousands of children and adults filmed or photographed themselves planting more than 10,000 trees, flowers, and other plants on six continents. The videos were consolidated and posted May 5 of last year on YouTube, where nearly 10,000 viewers, mostly children and young adults, commented on them.

The massive planting wasn’t a social project or contest, but a birthday present for Hank Green, the founder of the environmental-blogging site EcoGeek.com and a popular YouTube video blogger. Mr. Green’s ongoing video conversations with his brother, the young-adult book author John Green, often include original songs and debates about science topics, and have spawned a community of more than 470,000 who discuss current events, science, and other topics, and engage in regular group projects like the planting.

“To me, science is intrinsically cool,” Mr. Green said in an online interview with Education Week . “We may be a bunch of nerds, but when you see how much energy there is surrounding or growing knowledge of the world, it’s hard to not get caught up. And that’s really what we need; we need students to get caught up in the...