Eureka! The National Children's Museum is an interactive educational museum for children in Halifax, West Yorkshire, England, with a focus on learning through play. It is run as an educational charity and not-for-profit organisation. Eureka! is based on the North American model of children’s museums, aimed at families with children age 0–11 and encourages hands-on inter-generational learning.

Dame Vivien Duffield, Chair of the Clore Duffield Foundation, was inspired by the children's museums that she saw during visits to the USA. Back at home she pursued her idea to create the UK’s very own children’s museum, and The Museum for Children was formally constituted as a registered charity in 1985. Dame Vivien remains Eureka!’s Life President.

Eureka!'s location was partly inspired by Prince Charles, who opened the museum on 9 July 1992 and subsequently become its Patron until 2002.[1] It is located on former British Rail land next to Halifax railway station.

The building design was led by Ken Moth of Building Design Partnership, an international architectural practice, and the exhibition designs were produced by an in-house team and by design groups who pitched for various elements of the work – co-ordinated by Richard Fowler. Design groups included Imagination (the Me and My Body gallery) and Conran (original gift shop) and individuals included Tim Hunkin (Archimedes) and Satoshi Kitamura (illustrations).

Eureka! celebrated its 20th birthday in 2012 by launching - an online resource providing play ideas and campaign to get parents, carers and their children playing together.