Ten compassionate children from the Devonshire Road Primary School in the U.K. will be the youngest visitors ever invited to the European Parliament, on Wednesday, when they present an emotional and important anti-captivity poem.

The children began working on the poem when their teacher, Simon Hunt, reached out to Whale and Dolphin Conservation Society for background information to help his newest literacy project for the kids. Hunt, who had just watched Blackfish, wanted to use the growing movement against cetacean captivity as a writing topic for the children.

He started by showing them a video of the orcas performing, and the kids reacted as most kids would — they wanted to take a trip to see the orcas perform. But once the children were shown clips about how the orcas are taken from their homes and separated from their families, they wanted to spring to action.

Now, they’ve composed an emotional poem where the children take turns speaking in the voice of a captive orca. They will read the poem at an EU screening of Blackfish, as part of Dolphinaria-Free Europe, an event held in Brussels. Dolphinaria-Free Europe hopes to protect captive cetaceans through “investigation, advocacy and education,” and they hope to end the exploitation of animals in entertainment.

The harms of that exploitation are clear and poignant in the children’s poem. Watch it for yourself, and learn more about how captivity affects marine life.