"Children’s Museum" is a place of wonder for children, which takes them from the land of books to the land of objects. It encourages a child to probe new horizons. It directs children into constructive and worthwhile pastimes. It moulds them into sound citizens of the future.

The Children’s Museum of the Government Museum, Chennai consists of Basement, Ground floor and First floor, each having 5000 sq.ft. area. The architecture of the Children’s Museum conforms to that of a model museum building, with all the facilities contemplated in a modern museum. The display arrangements in the Children’s Museum reveals to the children the world in which they live, arouses intellectual curiosity and opens the door to the world of wonder.

Besides the galleries a fountain operated by solar power and water pumping unit operated by windmill, the life size Tyrannosaurus and Stegosaurus fibre glass models are the added attractions of the Children's Museum. Visitor facilities such as see through lift and a ramp way for physically handicapped visitors are available. It is a place where education is recreation and recreation is education.

The foundation stone was laid for the separate building for the Children's Museum in the Chennai Government Museum campus during the International Museum Week Celebrations in October 1956 AD, by His Excellency, Shri Sri Prakasa, the then Governor of Tamil Nadu. Plans were drawn and the cost was estimated to Rs.10.8 lakhs. However, unfortunately this proposal had to be deferred indefinitely. Therefore, it was felt necessary at least to start with a Children's Gallery. The exhibits that had been collected for this museum, along with a few specially prepared models and diagrams were provisionally displayed in fifteen newly made showcases, which were arranged in the mezzanine floor of the Geology Gallery. This newly organised Children's Gallery was thrown open to the public on the 'Children's Day' - 14th November 1960 AD.

Later, in September 1963 AD this Children's Gallery was shifted to the mezzanine floor of the newly constructed Natural History Block where the exhibits were re-arranged and re-exhibited. The proposal of constructing a separate new building for Childrens Museum was renewed in 1979 AD during the International Year of Children, and completed by incurring an expenditure of Rs.39 lakhs. Display was organised in modern way, including the existing exhibits of the Childrens Gallery. His Excellency, Dr. P.C. Alexander, the Governor of Tamil Nadu inaugurated this newly organised Childrens Museum, on 11th April 1988 AD.

In 1996 - 1997 AD, the Civilisation Gallery and Physical Science Gallery were reorganised with new showcases. In 1998 - 1999 AD, the Technology Gallery was established with working models in new aluminium showcases. Many developmental projects are in the anvil.