We like to think that we're pretty good at math, especially after years of schooling. But every once in a while, a simple third-grade math problem manages to trip us up and make us question our ...

It's a math puzzle designed for third graders, but many adults are having trouble solving it. The puzzle looks something like Scrabble, with a series of boxes that snake up, down and across a page.

The designers for Monte Vista Elementary School’s proposed outdoor classroom had some key questions to answer: What materials could they use while staying under the district’s $10,000 budget? How much ...