After an assistant in the third-grade classroom at Garnet Valley School led the kids in stretching exercises, counted down the time for their writing assignment, and finally blared the Village People’s “YMCA” from a speaker for a fast and furious dance break, a student blurted something out.

“I love her!” said Kaidyn Potochar, one of the third graders.

“I love her, too,” agreed her teacher, Meredithe Stefanowicz, but the assistant fell silent. She sat perched on a small counter, less than a foot tall.

You’ve probably heard of her: Alexa.

The Delaware County school is considered a trailblazer in using the fast-growing technology of digital voice assistants — like Amazon’s Alexa, the most popular, or Google Assistant — as a classroom learning tool that can answer a student’s question or spell a word, conduct learning drills, or play soothing background music while timing out a quiz.

“What’s really funny is that they listen to Alexa a lot more cheerfully than they listen to us,” said Marianne Maye, a second-grade teacher at Concord Elementary in Garnet Valley, one of just four districts in the country taking part in a yearlong pilot program with a pioneering developer of an Alexa app for schools called askMyClass.

”This is what this generation has at their fingertips, or lips, so to speak,” added Maye, who has been teaching 36 years, “and if I don’t become part of their generation — their experience — then I’m not going to be as effective.”

About one-quarter of U.S. homes now boast a smart speaker such as Amazon Echo — host for its Alexa voice assistant — or Google Home, and most of these devices were purchased in the last year or so, according to a 2018 report by Nielsen. And while the global tally of voice assistants is expected to triple to a whopping eight billion by 2023, a separate report found, schools are just beginning to grasp the possibilities of this new technology.

A handful of start-ups like askMyClass — which works to both winnow down and refine 30,000 potential Alexa functions to host those that are appropriate for kids and can help them in class — promise that a tiny smart speaker can act as a second set of hands for today’s overworked teachers, performing tasks that range from answering student questions to playing math games or promoting mindfulness.

“There are thousands of voice apps on Alexa, all basically with a single purpose or function,” said Aparna Ramanathan, who cofounded Silicon Valley-based askMyClass with her husband, Deepak, last year after running a 2017 pilot project. “It might be for a dance break or a [class] lineup — our purpose was to bring it all together, so in one place you can access what you need for a classroom.”

Ramanathan, a physician, and her husband, who formerly worked for Google, said she began thinking about how voice assistants like Amazon’s Alexa might aid the health and well-being of children not long after the technology started hitting the market nearly five years ago. Their 2017 pilot project began with 20 teachers testing the app — which can be used on other devices besides Amazon Echo —and eventually grew to 200.

“The teachers that use it are amazing, they have so many ideas that we struggle to keep up in developing things,” said Ramanathan, whose firm attends technology shows and competes with other education-focused third-party start-ups such as rival ClassAlexa.

Since last fall’s official launch, askMyClass has partnered with four districts — including Garnet Valley, where 31 teachers now use it, as well as New Jersey’s Monroe Township and districts in Wisconsin and Ohio — to integrate the Alexa technology throughout a school. Nationwide, about 1,000 classrooms are using the new app, which cost $20 per teacher after a free trial.

The cost to Garnet Valley is $2,400, or $80 per classroom, for the device and app.

Szymon Machajewski, a professor in computing and information systems at Michigan’s Grand Valley State University and an early adapter in using Alexa in his college classroom, acknowledged there are some privacy concerns over devices like the Echo that can record children’s voices and sends those data to Amazon’s computing cloud — an issue that’s also been raised by the American Civil Liberties Union.

Machajewski said there are other hurdles with integrating the Alexa technology — the multiple voices of a crowded classroom of younger kids can confuse the device, for example.

Stefanowicz became one of the first teachers in the nation to join the askMyClass pilot project after reading about it from other educators she follows on social media and going in with her mom, also a teacher, on a special offer to buy two Echo devices for $50.

On a recent classroom visit, Stefanowicz guided the device by starting commands with the words Alexa, ask my class. … For an indoor recess activity, her students played Animal Guess Who, in which Alexa recited clues while children acted out various animals until they guessed the answer was a snake. During a class writing exercise, soft music emanated from the speaker, punctuated occasionally by students walking up and asking Alexa how to spell a word.

“They’re exposed to so much in their world that it’s just background noise,” Stefanowicz said, referring to concerns from administrators that the device might be distracting. “They don’t even look up.” Indeed, she said students sometimes pay closer attention when the machine speaks than when she does.

Maye said learning to use Alexa in class, especially for veteran teachers who have their own routines, “is like a diet or exercise routine -- you have to work at forming routines and if you keep at it, it becomes instinct.” Some of her favorite uses have been a morning greeting where Alexa teaches kids how to say “good morning” in a foreign language, or using the device as a “class picker” that randomly assigns kids to a project.

Stefanowicz said the biggest problem is the occasional and inevitable technological glitch. “If the WiFi is down,” the teacher said, “it’s like our friend is not there.”