Educators have long been wary of cellphones. They're a distraction, a tool for cyber-bullying and the ultimate cheat sheet for any quiz or exam.
To make matters worse, banning them is next to impossible: The devices are getting smaller and more discreet, and ringtones are available that buzz outside the audible range of hearing of most adults.
But the growing consensus is that cellphones are no longer the enemy, and educators have begun harnessing the pedagogical potential of texting, collaborative Google docs and GPS capabilities.
In perhaps the strongest evidence of this shift, the Toronto District School Board, Canada's largest, which went to the extreme four years ago of banning cellphones in its schools, decided early Thursday morning to let them back in - though a number of terms and conditions will apply.
The growing capabilities and applications for phones have forced teachers to see them in a new light, according to Kevin Kee, Canada Research Chair in Humanities Computing at Brock University.
"There's traditionally been a lot of anxiety about phones in the classroom, but the truth is now that they're small computers that just happen to do phone stuff," he said.
Many school boards leave principals to make their own policy on cellphones. But Toronto isn't the only large board to ban them outright - they've long been banished from New York classrooms.
At the other end of the spectrum, a school district in Auburn, Maine, recently bought an iPad for each of kindergarteners after teachers noticed the gadgets improved literacy.
Another district, the Onslow County School System in North Carolina, hosted a pilot called Project K-Nect that provided smartphones to Grade 9 students who were struggling in math. Teachers texted supplementary questions to the phones, and students used them to access virtual classrooms and tutoring. The devices seemed to engage students more in their classes, and they were texting and exchanging videos about them after school, according to Shawn Gross, the project's director.
"The thing that's been most impressive to us is these students have developed these personalized learning communities, so there's a lot going on in the after-school hours," he said.
At the end of the first year of the project, more than 90 per cent passed their end-of-year exam. In an independent evaluation scheduled to be released next week, after four years in the programs most of the students went on to complete Advanced Placement math courses.
Dr. Kee says the learning potential of phones keeps growing, and there are even apps being built that can guide students through local history lessons by having GPS-guided ghosts pop up on their smartphones to talk about landmarks and historical events.
Technological and educational innovations are winning over even the staunchest critics.
Steve Gray, principal of the Port Hardy Secondary School on the north coast of Vancouver Island, became so frustrated with students abusing their cellphones that he bought a jamming device to block reception throughout his high school. The jamming only lasted a few days - turns out it's illegal - but it made him a celebrity.
"I was more popular than I've ever been in my life," he said. "… It wasn't just parents. I had old ladies in the parking lot at the local food store giving me hugs."
Today, two years later, Mr. Gray accepts that cellphones will continue to infiltrate the classroom. He said a teacher at another high school in his district is promoting class participation by polling students via text message, Who Wants to Be a Millionaire-style.
"I think where we're going is electronic textbooks you'll use on your cellphone," he said.
Cellphones won't permeate Toronto's schools in this way next fall, when the new rules take effect. They will be allowed in the classroom only for educational purposes and with the permission of the teacher, and in the hallways as long as they're not disruptive.
But it may be just a matter of time.
"Way back," said Chris Spence, the TDSB's director of education, "I remember having the same discussion about calculators."