Schools are being invited to break the world record of the most youngsters singing and signing a song.
Teachers, parents and children from the borough have until January 23 to register for SignHealth's sign2sing world record breaking attempt.
Schoolchildren from across the UK and overseas will learn to sign a song called sign2sing designed especially for the event.
The event is aiming to raise awareness of deafness, as well as acting as a fundraiser, with everyone paying a donation to take part.
Money raised will be used to help SignHealth improve the mental and physical health of deaf people.
Steve Powell, chief executive of the charity, said: "More than 900 schools, including Spring Park Primary School in Shirley, Croydon, have so far signed up for sign2sing but we are hoping around 1,200 schools will participate to ensure we break our current world record.
"Last year 14,277 children took part in our second sign2sing event and broke our previous record. We are once again inviting schoolchildren and also parents, if they’d like to join in, to take part in our Guinness World Records attempt for the most people signing and singing a song at the same time."
The event is taking place on February 6.
Any schools interested in taking part can visit sign2sing.org.uk