LANSING — Michigan will face an education crisis that will harm children if policymakers don’t address a teacher shortage that has sparked an explosion in untrained substitutes leading classrooms.

That was the conclusion of a panel of experts who spoke Thursday at a summit sponsored by Bridge Magazine and its parent company, The Center for Michigan, at Lansing Community College.

More than 2,500 Michigan classrooms were led by long-term substitutes who weren’t certified during the 2018-19 school year, a tenfold increase in five years, according to a Bridge Magazine analysis published in August.

Low-income and academically struggling students are most likely to be taught by the instructors, who aren’t required to have a four-year degree or any teacher training, according to Bridge’s analysis. That’s because of a policy meant to fill classroom vacancies that allows those with as few as 60 college credits in any subject to teach a class for a full year.

“That is verging on a crisis,” said Elizabeth Birr Moje, dean of the University of Michigan’s School of Education. “We know that great instruction matters, and we know that teachers who are not prepared are not providing great instruction.”

Moje and other experts called the long-term sub trend a symptom of institutional problems that have underpaid teachers and left them with fewer classroom resources, diminished respect and looking for another career.

Higher pay and more classroom funding would attract teachers to Michigan, several panelists said. But changing rhetoric about the profession is important too, some argued. That could include touting the profession as a vehicle for social change and justice — as well as toning down rhetoric focusing solely on teacher accountability.

“Let’s stop talking about teachers as if they’re idiots,” said Moje, adding that her school is trying to tell positive stories about teaching.