Bridge Bao

Bao built his first real bridge when he was small, across a creek behind his house.

The creek was too wide to jump. For a long time he just stood on his side, staring at the far bank, certain he could never get there. Then his aunt, who built actual bridges for a living, crouched next to him.

"You're looking at the whole gap," she said. "Don't. Look at the nearest solid thing." She pointed to a flat rock, close to his side. "Stand there. Now what's the next solid thing you can reach from that?" A log, a little further. Then a sandbar. Then the far bank. "You never crossed the whole creek at once," she told him after. "You crossed one small reachable step at a time, each one from solid ground."

Bao took that to heart, and then he took it to numbers. He noticed he didn't actually need to memorize every fact. He needed a handful of solid ones — the fives, the tens, the doubles — and then he could reach any other fact by stepping out from the nearest solid one. Nine sevens? Start from ten sevens, which is easy: seventy. Step back one seven: sixty-three. Seven eights? Start from the double of the double — he had a dozen little bridges, each one anchored on a fact he was sure of.

He stopped feeling like there was an endless wall of facts to cram. There was just solid ground, and short steps, and bridges he could build on the spot.

The bridges worked in every direction, Bao showed kids — step forward, step back, double, whatever was shortest from solid ground.

A boy named Sef was stuck on *9 × 8.*

"Nine is so close to ten," Bao said. "And ten times eight is the easiest thing alive: eighty. So stand on eighty. Now, nine eights is one fewer eight than ten eights. Step back one eight: eighty minus eight is seventy-two." He spread his hands like a finished bridge. "Nine times eight is seventy-two. You started on a fact you were sure of, and took one short step back."

Sef tried another, reaching from a fact he knew toward one he didn't, taking the shortest step he could find. "I keep thinking I don't know these," he said slowly, "but I always know one that's close."

"You always do," Bao said. "Nobody starts from nothing. There's always solid ground nearby. The skill isn't knowing every fact. It's knowing how to step out from the ones you've got."

Sef wrote: Start from a fact I know. Take the shortest step to the one I don't.

What Bao wanted most was for kids to stop believing the lie that they "knew nothing."

"That's the feeling that beats people," he told a girl named Priya, who shut down the second a fact felt unfamiliar. "Not the math — the thought. 'I don't know this, so I'm stuck.' But you're almost never starting from nothing." He gestured at an imaginary gap. "There's always a fact near the one you want — a five, a ten, a double, something. Find that solid spot, stand on it, and reach. You don't have to leap the whole creek. You just have to take one step from the nearest rock."

Priya looked at a fact that had scared her, and instead of freezing, she went looking for the nearest thing she did know. She found it. She took one step. The new fact was just... there, on the other side of a tiny bridge.

"I wasn't starting from nothing," she said, sounding almost relieved.

"You never were," said Bao.