Schools are supposed to be where our children are encouraged to develop new interests and skills and prepare for their future as engaged and productive adults. But immigrant students across Maine are facing relentless harassment that tells them they’re not welcome in the state’s K-12 public classrooms – with bleak consequences for newcomers and those born here alike.

The American Civil Liberties Union of Maine study “We Belong Here,” which draws on over 115 interviews with parents, educators, community leaders and students, found “a constant barrage of bullying” across Maine at all grade levels. And what’s recounted in the new report goes far beyond mere teasing.

• Students of color are being called the N-word, told to “Go back to Mexico” or threatened with deportation.

• The classmates of Muslim young people are addressing them as “ISIS” or trying to pull off their headscarves.

• Bus drivers are refusing to pick up immigrant children or openly ridiculing them and encouraging other students to join in.

• Teachers are turning a blind eye to bullying or telling immigrants that they’re not cut out for challenging classes.

Even predominantly white Maine schools aren’t exempt from considering their obligations to minority students. Bullying is not only ugly but also a violation of both state and federal law. Schools that don’t take steps to address discrimination risk state human rights investigations, student lawsuits and federal prosecution. Harassment is, as well, a moral failure – one that makes some students feel afraid when they’re in school and prompts others to drop out altogether, putting them on a path to lower achievement and depriving the community of their potential.

Of course, even schools with a poor track record on diversity have teachers and administrators who are supportive of immigrant students and work to meet their needs. But a high school educator told the ACLU that it can be tough to make a difference when everyone around them buys in to pernicious myths – like the idea that immigrants come here to live off welfare or take American jobs.

Yes, it can be expensive to resettle refugees in the United States. The cost of health care, food stamps, cash assistance and other direct and indirect aid adds up to about $180,000 per person, Notre Dame economist William Evans recently told National Public Radio. So for their first nine years in the U.S., refugees cost more in services than they pay in taxes. After that, though, they start paying in more than they’re taking out – and by the time they’ve lived here for 20 years, Evans found, refugees “will have paid an average of $21,000 more in taxes than in benefits received … since arrival.”

That fits with an internal U.S. Health and Human Services Department study, prepared this summer, that determined that refugees brought in $63 billion more in tax revenue than they cost between 2005 and 2014.

The people perpetrating the harassment and those who are enabling it may never recognize the high cost we all pay when some of us are deprived of a safe place in which to learn. But the Maine schools that make a commitment to making room for immigrants (the ACLU report highlights different ways this can be done) will find out that the benefits of doing the right thing can be significant as well.