Superior High School student Ari Robillard, second from left, reacts as her teammates, Taylor Schultz, left, and Paige B. Johnson balance a weighted bucket on their toothpick bridge at the American ...

Seventh-grader Jacoby Yliniemi dropped a bowl of sand into the bucket being held up by his group’s toothpick bridge, bit his lip and then relaxed. The bridge was safe. At least for a second. Another ...