About 70,000 deaf people in the UK have British Sign Language as their first language, and at this school in London, everyone is learning it.
Deaf pupils at the school have been helping their hearing friends to learn sign language.
More than 30,000 people have signed an online petition saying that everyone should learn sign language at school.
The Department of Education says that it would be too difficult for all schools to have to teach sign language, but "schools are free to teach it if they choose to do so."
The kids at this school told us what they think.