Another student, Kevin Kent, said the ball makes it easier for him to concentrate and keeps his back from getting stiff. Now, he said, sitting in a chair is "weird, because you're all bent up."
Some health experts cautioned against the possibility of student horseplay and falling off the balls. But Giuliano's 24 students know they must keep their bottoms on the balls and feet on the floor at all times, though they can bounce and bob as much as they like.
The same goes for Dannielle Doran's fourth-graders at Merion Elementary School in a nearby district, where misbehavior risks loss of the ball and a return to a four-legged seat.
"They like sitting on them so much, and they don't want to lose that privilege," Doran said. "It seems to almost ... motivate better behavior."
At Namaste Charter School in Chicago, which is guided by the philosophy that healthy and active kids perform better in class, all students learn to use stability balls during physical education.
Yet they're used as seats in academic settings only on a case-by-case basis, principal Allison Slade said.
"Fifth-graders are so antsy that, for some kids, this is really good for them," Slade said. "But for others, I think it could be really distracting."
To be sure, the balls are not mandatory in Doran's or Giuliano's classes, but Giuliano noted only one student in three years has opted to continue using a chair.
Parents have been supportive as well, voluntarily purchasing the $5 balls for their kids. Some even ended up buying balls for themselves to use at home and work, said Giuliano, who wants to spread the word to other teachers.
"I don't like sitting on a chair all day ... so I started sitting on a yoga ball, and I find I'm more alert," Giuliano said. "And my message is to try it with your class and see if it works for you."
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