In 1885, businessman and philanthropist Gan Eng Seng opened a school at several shophouses in Telok Ayer Street to provide free education to children of poor residents in the vicinity.

Despite being forced to close for a few years during the Japanese Occupation, Gan Eng Seng School has continued to thrive, and celebrated its 130th anniversary in 2015.

This photograph of its students was taken in 1951. That was the year the school moved from its premises in Waterloo Street to Anson Road. The school is now located in Henderson Road.

This week, The Straits Times features four black-and-white photos from the Singapore Press Holdings' archives that were colourised using the Government Technology Agency's new and free online tool that adds colour to old black-and-white photos almost instantly.

The tool, called Colourise.sg, takes about 3-1/2 seconds to add colour to an uploaded photo.