A teenager performing a yo-yo trick

A CHAMPION PERFORMS: Betty Gallegos in competition

COURTESY OF YOYO FACTORY

STANDARDS

NGSS: Core Idea: PS2.A

CCSS: Literacy in Science: 2

TEKS: 6.8A, 6.8B, 6.8D, 7.2D, 8.6A, P.2E, P.2J, P.4A

Yo-Yo Wizards

Young people from around the world show off mind-blowing yo-yo tricks

AS YOU READ, THINK ABOUT the forces that help keep a yo-yo in motion.

When Betty Gallegos was 12, she and her mom stumbled across a yo-yo competition in a park near their home in Mexico City. Gallegos watched in awe as participants whipped their yo-yos into the air, rapidly looping their strings into complex patterns around their fingers and arms. The competitors then bounced their yo-yos through the webs they’d made—all while keeping the toys spinning and their strings from becoming a tangled mess.

When Betty Gallegos was 12, she and her mom went to a park near their home in Mexico City. There, they happened upon a yo-yo competition. Gallegos watched in awe as people threw their yo-yos into the air. They quickly looped their strings into complex patterns around their fingers and arms. Then the competitors bounced their yo-yos through the webs they’d made. At the same time, they kept the toys spinning and their strings from becoming a tangled mess. 

COURTESY OF YOYO FACTORY

IN THE ZONE: Betty Gallegos

Afterward, Gallegos’s mom bought her a yo-yo. She practiced for years until she could master many of the stunts she’d seen—even inventing a few of her own. Gallegos, now a 21-year-old college student, is part of a worldwide community of more than 10,000 competitive yo-yoers. They practice for hours a day, share tutorials on YouTube, and show off their tricks at national and international championships.

During competitions, yo-yoers like Gallegos perform two- to three-minute choreographed routines in time to music. Judges award points based on artistry, level of difficulty, and how well contestants execute tricks. Competitors rely on their skill to ace their performances. But they also get a little help from specially designed yo-yos. These high-tech toys harness physics to spin faster and longer, allowing for truly spectacular stunts.

Afterward, Gallegos’s mom bought her a yo-yo. She practiced for years, and she finally mastered many of the stunts she’d seen. She even invented some of her own. Gallegos is now a 21-year-old college student. She belongs to a worldwide community of more than 10,000 competitive yo-yoers. They practice for hours every day and share training videos on YouTube. They also show off their tricks at national and international championships.

Yo-yoers like Gallegos perform for two to three minutes during competitions. Their routines are planned in time to music. Judges give points for creative skill, difficulty level, and how well the tricks are done. Competitors need skill to ace their performances. But they also get a little help from specially designed yo-yos. These high-tech toys use physics to spin faster and longer. That allows for truly amazing stunts. 

YO-YO BASICS

After witnessing her first competition as a kid, Gallegos found a group called the Mexican Yo-Yo Association. It offered free yo-yo lessons to local kids and set up workshops that Gallegos began to attend. There, she says, “I started to learn basic tricks like The Sleeper.” This simple maneuver, where the yo-yo keeps spinning at the end of its string, is the first step in any professional routine (see Tricky Techniques).

To make a yo-yo “sleep,” Gallegos throws it toward the ground. As the yo-yo leaves her hand, it has stored potential energy because of its elevated position, explains Maria Holland. She’s a mechanical engineer at the University of Notre Dame in Indiana. The force of gravity then pulls the yo-yo downward, turning potential energy into kinetic energy, or energy of motion. As the yo-yo falls, the string wrapped around its central axle unwinds, causing the yo-yo to rotate. It continues to spin when it reaches the bottom of the string.

After Gallegos watched her first competition as a kid, she found a group called the Mexican Yo-Yo Association. It offered free yo-yo lessons to local kids and set up workshops. Gallegos began to attend. There, she says, “I started to learn basic tricks like The Sleeper.” In this simple move, the yo-yo keeps spinning at the end of its string. It’s the first step in any professional routine (see Tricky Techniques).

To make a yo-yo “sleep,” Gallegos throws it toward the ground. When the yo-yo leaves her hand, it has stored potential energy. That’s because of its raised position, explains Maria Holland. She’s a mechanical engineer at the University of Notre Dame in Indiana. Then the force of gravity pulls the yo-yo downward. This turns potential energy into kinetic energy, or energy of motion. The yo-yo’s string is wrapped around its central axle. As the yo-yo falls, the string unwinds, making the yo-yo rotate. It keeps spinning when it reaches the bottom of the string.

To “wake” the yo-yo back up, Gallegos loops its string around its axle. Then she gives the string a quick tug. That creates friction between the loop of string and the yo-yo. Friction is a force that resists movement when surfaces rub against one another. “You’re trying to increase friction to the point where it will be easier for the yo-yo to rotate around the string than to keep rubbing against it,” says Holland. Once that happens, the yo-yo winds back up the string to Gallegos’s hand, ready to be thrown again for her next trick.

To “wake” the yo-yo back up, Gallegos loops its string around its axle. Then she tugs quickly on the string. That creates friction between the loop of string and the yo-yo. Friction occurs when surfaces rub against each other. It’s a force that resists movement. “You’re trying to increase friction to the point where it will be easier for the yo-yo to rotate around the string than to keep rubbing against it,” says Holland. When that happens, the yo-yo winds back up the string to Gallegos’s hand. It’s ready to be thrown for her next trick.

TRICKED-OUT DESIGN

During a yo-yo contest, Gallegos has only a few minutes to wow the judges. To earn the most points, she needs to do as many tricks as possible while the yo-yo sleeps. If the yo-yo’sspinning slows, she’ll have to bring it back up and toss it again, losing precious time during which she could be performing stunts.

During a yo-yo contest, Gallegos has only a few minutes to wow the judges. She needs to do as many tricks as possible while the yo-yo sleeps. That’s how to earn the most points. If the spinning yo-yo slows, she’ll have to bring it back up and toss it again. Then she’ll have less time to perform tricks.

That’s why competition yo-yos are designed to maximize how long they sleep on each throw. They’re more like precision tools than the classic toys kids have been playing with for thousands of years. Originally, yo-yos were made of heavy wood. Each had a solid axle that its string looped around. These yo-yos can sleep briefly but quickly slow down as friction builds between the yo-yo and the string. “Every time it spins, [friction] is stealing a little bit of energy from the yo-yo,” explains Holland. That can go on for only so long before the sleeping yo-yo runs out of steam.

Professional yo-yos, on the other hand, are often made of lightweight aluminum (see Inside a Yo-Yo). Their edges are weighted to increase rotational inertia—an object’s tendency to keep rotating—while the yo-yo sleeps at the end of the string. To reduce friction, a modern yo-yo also contains a ball bearing. It consists of two rings that wrap around the central axle. Between the two rings are tiny metal balls that allow the rings to smoothly glide past one another. The yo-yo string coils around the outer ring, while the inner ring spins with the yo-yo.

That’s why competition yo-yos are designed to sleep a long time on each throw. They’re carefully-made tools, not the classic kids’ toys used for thousands of years. At first, yo-yos were made of heavy wood. A yo-yo’s string looped around a solid axle. These yo-yos can sleep briefly, but they quickly slow down. That’s because friction builds between the yo-yo and the string. “Every time it spins, [friction] is stealing a little bit of energy from the yo-yo,” explains Holland. That can go on for only so long. Then the sleeping yo-yo runs out of steam.

But professional yo-yos are often made of lightweight aluminum (see Inside a Yo-Yo). Their edges are heavier to increase rotational inertia, an object’s tendency to keep rotating. That helps keep the yo-yo sleeping at the end of the string. To reduce friction, a modern yo-yo also contains a ball bearing. It’s made of two rings around the central axle. Tiny metal balls are between the two rings. They allow the rings to smoothly slide past one another. The yo-yo string wraps around the outer ring, and the inner ring spins with the yo-yo. 

COURTESY OF YOYO FACTORY (NAGAO); ROBERT GAUTHIER/LOS ANGELES TIMES VIA GETTY IMAGES (STEIN)

  • SPINNING STRONG: 2018 World Yo-Yo Champion Evan Nagao
  • FLYING HIGH: Pro yo-yoer Gentry Stein

PRACTICE MAKES PERFECT

Last April, Gallegos became the first female competitor to win the co-ed Mexican National Yoyo Championship. She then spent all summer preparing her routine for the World YoYo Contest held in August in Cleveland, Ohio. Gallegos would be one of more than 200 yo-yoers from 21 countries vying for prizes at the event. Her competitors were some of the best yo-yoers in the world, so she knew her routine needed to be amazing. She worked on it every night for up to three hours. “I couldn’t go to sleep knowing that I hadn’t practiced that day,” she says.

Last April, Gallegos competed in the co-ed Mexican National Yoyo Championship. She became the first female to win it. Then she spent all summer preparing her routine for the World YoYo Contest. It was held in August in Cleveland, Ohio. More than 200 yo-yoers from 21 countries competed for prizes at the event. Her competitors were some of the best yo-yoers in the world, so she knew her routine needed to be amazing. She worked on it every night for up to three hours. “I couldn’t go to sleep knowing that I hadn’t practiced that day,” she says.