We don’t look at polka dots twice. Our brains immediately recognize that they’re a repeating pattern of dots. The same goes for plaid, chevron or any kind of design. We’re also able to look at a bunch ...

Teacher Leticia Denoya stands at the front of her classroom, at Natchaug Elementary in Windham, Conn. Her first-graders sit criss-cross applesauce on the reading rug. "Do you remember last week, we ...