A Massachusetts mother touring a kindergarten on Wednesday to determine what to expect when her 5-year-old daughter starts school in the fall saw a “jarring” poster instructing children how to behave in the case of a lockdown.

Georgy Cohen encountered the poster at Sommerville Public School, snapped a photo and posted it on Twitter. Her tweet has since gone viral, The Boston Globe reported.

The poster, designed to teach kindergartners what to do during a lockdown or drill, features a poem intended to be sung to the tune of “Twinkle, Twinkle Little Star.”

The poster reads: “Lockdown, lockdown. Lock the door. Shut the lights off. Say no more. 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!”

Although Cohen was glad that the school was teaching children what to to in the event of a lockdown, she was taken aback by the poster.

“When I was in kindergarten, we had fire drills. It was different — we didn’t have these same types of threats,” Cohen said. “These are the things they unfortunately have to do. I get it.”

Cohen was encouraged by the response to her tweet, which has received more than 35,000 likes since it was posted on Wednesday morning.

“To be shocked by it is important. To see that absurdity and horror and have that sick feeling in your stomach is important,” Cohen said. “Stay outraged. And if it gets somebody to do something — to give money to an organization or to call their representatives … then great, I think that that’s important.”

According to The Hill, “Somerville Public School officials have not yet released a statement on the lockdown directions and it is unclear whether it’s mandatory for them to be displayed in the school’s classrooms.”