For the first part of Doug Pray’s arresting documentary, the lifestyle of Dorian Paskowitz and his flock of nine children offers a defiant challenge to the ho-hum straight world, as they traverse America in a 24-foot van, stopping wherever there’s a spot to surf. Life is always a vacation, work and school be damned. Better still, many of the Paskowitz clan become renowned prize-winning surfers. In the second part, the utopian road movie skids into the ditch, with sobering tales from the now grown-up and maladjusted siblings about how their controlling father, a Stanford graduate and medical doctor, kept them from any real education. Only at the end does this work significantly misstep, with a clichéd “heartwarming” family reunion surely orchestrated by the filmmaker. 93 minutes | Kendall Square