The little rhyming song is about what to do in case of a school shooting or similar situation.
It continues: "Go behind the desk and hide, wait until it's safe inside. Lockdown, lockdown, it's all done. Now it's time to have some fun."
Cohen posted a photo of the poster on social media writing; "This should not be hanging in my soon-to-be-kindergartener's classroom."
As debate around gun control continues to rage in America, her Twitter post quickly spread across the internet, racking up more than 22,000 comments.
"This country is a horror movie," wrote a different Twitter user who posted Cohen's photo separately, receiving more than 133,000 likes and 46,000 retweets.
Cohen who didn't want to identify the school told The Boston Globe that the "jarring" sign was a far cry from the fire drills she had as a young student and lamented the state of the country after a string of school shootings.
"It was different — we didn't have these same types of threats," she told the newspaper. "These are the things they unfortunately have to do ... I get it."
Plenty of people chimed in on social media, decrying the harsh reality encapsulated by the poster.
Cohen said she was pleased that her post had garnered such a strong reaction on Twitter and was quick to engage in debate about the issue of gun control with other users.
"To be shocked by it is important," she told The Globe. "To see that absurdity and horror and have that sick feeling in your stomach is important. Stay outraged. And if it gets somebody to do something — to give money to an organisation or to call their representatives — then great, I think that's important."
The poster adorned the wall of a school in Somerville in the state of Massachusetts. As the story of the classroom song went around the world, the local Somerville Mayor Joseph Curtatone and Somerville Public Schools Superintendent Mary Skipper issued a joint statement to media saying the poster reflects the reality for students across the country.
"As much as we would prefer that school lockdowns not be a part of the educational experience, unfortunately this is the world we live in," the statement read. "It is jarring — it's jarring for students, for educators, and for families.
"Students in Somerville and across the country know how unnatural this is, as evidenced by their vocal leadership and advocacy this year in response to continuing school shootings."
Such drills have become common practice in classrooms across the United States and teachers say songs like this one can help the younger students stay calm and remember the steps they need to take in such situations.
