In 1985, a pediatrician named Mark Wolraich put 16 hyperactive boys on a sugar-free diet for a day, then gave each of them a drink. Some got sugar. Some got an artificial sweetener. The researchers found no difference in behavior or cognition between the two groups. Wolraich ran a three-week double-blind trial in 1994 and got the same result, and his 1995 review of 23 studies concluded that sugar does not affect children’s behavior or cognitive performance.

Olga Khazan runs through that record in The Atlantic this week, under the headline “A Halloween Myth That Can Finally Die.” The myth survives, she writes, because candy shows up at birthdays and Halloween, where the noise and the costumes are doing the work. It also survives because parents expect it to be true. In one study she cites, mothers told their kids had eaten a large dose of sugar rated them as significantly more hyperactive than mothers told their kids got a placebo. Every child had gotten the placebo.

Schools carry their own set of these. Two Octobers ago, ISTE+ASCD CEO Richard Culatta published “Attack of the Zombie Learning Theories!,” borrowing researcher Bryan Goodwin’s term for ideas about learning that research has killed but that still walk the halls. His list includes learning styles, left brain versus right brain, the 10,000-hour rule and multitasking.

The data on how many educators believe them is uncomfortable. A 2017 survey of 598 educators who took an online brain quiz found 76 percent agreed that people learn better in their preferred learning style, 49 percent agreed that some of us are left-brained and some right-brained, and 50 percent agreed that children are less attentive after sugary snacks. The authors note their respondents were more likely than the average teacher to hold a graduate degree, so they describe those numbers as the best case.

Some of it arrives through training. A 2016 National Council on Teacher Quality review of 48 teacher-preparation programs found 67 percent required candidates to work learning styles into lesson plans.

Khazan’s practical advice for Friday: the American Heart Association caps added sugar for kids at 25 grams a day, about three fun-size packs of M&Ms, and University of Utah pediatrician Gwen Cook told her that blowing past it on Halloween is fine.

🎃 A question for Halloween week: What education myth still haunts you? A claim that keeps resurfacing in meetings, a fact you learned in school and later had to unlearn, or something you once confidently repeated yourself. Hit reply.

— Thomas

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