Craven grew up in Silverton, Oregon and graduated from the University of Puget Sound in Tacoma, Washington. In 2007, when he was a science teacher at Central High School in Independence, Oregon, Craven posted the nine and one-half minute "The Most Terrifying Video You'll Ever See" on YouTube, an appeal to act on climate change.

In the first six months online it garnered four million hits, and prompted Craven to spend six weeks creating 44 follow up videos totaling over six hours detailing specifics of risk management applied to climate change. Craven's conclusion is that "the risk of not acting far outweighs the risk of acting." Craven was the focus of some media attention, was named "Featured Teacher" by WIRED Science, and received criticism by climate change skeptics. In 2009, Craven published the book What's the Worst That Could Happen?: A Rational Response to the Climate Change Debate.