The new computer, similar to the Raspberry Pi, will be given to 11 or 12-year-olds in year 7 across the UK, for free.
The BBC first introduced many school children to computing for the first time in 1981, when it produced its BBC Micro. Today's giveaway is part of its 2015 Make It Digital initiative, inspiring young people to be creative and develop core skills in science, technology and engineering.
Partners involved in the development and distribution of the micro:bit include ARM, Barclays, BBC, element14, Freescale, Lancaster University, Microsoft, Nordic Semiconductor, Samsung, ScienceScope, Technology Will Save Us and the Wellcome Trust.
Tony Hall, Director-General of the BBC said: "Channelling the spirit of the Micro for the digital age, the BBC micro:bit will inspire a new generation in a defining moment for digital creativity here in the UK. All you need is your curiosity, creativity and imagination - we'll provide the tools. This has the power to be transformative for the UK. The BBC is one of the few organisations in the world that could convene something on this scale, with such an unprecedented partnership at its core."
Measuring 4cm by 5cm, the micro:bit is available in a range of colours and is designed to be fun and easy to use, allowing children to transition to more complicated codeable boards like the Raspberry Pi or Arduino in the future.
It will allow children to code simple tasks in "seconds", like lighting up its LEDs or displaying a pattern - with no prior knowledge of computing.
It also connects to other devices, sensors, kits and objects.
Key features include:
Each element of the BBC micro:bit is completely programmable via easy-to-use software on a dedicated website (available later in the summer at microbit.co.uk) that can be accessed from a PC, tablet or mobile. The website allows children to save and test creations in a simulator before they are transferred to the micro:bit.
Sinead Rocks, Head of BBC Learning, said: "We happily give children paint brushes when they're young, with no experience - it should be exactly the same with technology. The BBC micro:bit is all about young people learning to express themselves digitally, and it's their device to own. It's our most ambitious education initiative for 30 years. And as the micro:bit is able to connect to everything from mobile phones to plant pots and Raspberry Pis, this could be for the internet-of-things what the BBC Micro was to the British gaming industry."