The device – which features a programmable array of red LED lights – includes two buttons and a built-in motion sensor that were not included in a prototype shown off in March.
But another change means the product no longer has a slot for a thin battery.
That may compromise its appeal as a wearable device.
An add-on power pack, fitted with AA batteries, will be needed to use it as a standalone product.
The BBC’s director general Tony Hall said the device should help tackle the fact children were leaving school knowing how to use computers but not how to program them.
“We all know there’s a critical and growing digital skills gap in this country and that’s why it’s so important that we come together and do something about it,” he said at a launch event in London.
Children will be encouraged to write simple code for the Micro Bit via a new website, which will be accessible on both PCs and mobile devices.
They will be able to save and test their programs on the site before transferring them to the tiny computer via a USB cable or wireless Bluetooth connection.
The Micro Bit can then be made to interact with its built-in sensors and buttons to make its 25 LEDs flash in different patterns, letting it display – for example – letters and numbers.
In addition, it can be connected to other computing kit via its input-output rings – including the Raspberry Pi, Arduino and Galileo – to carry out more complex tasks.
For More Details: BBC Micro Bit computer’s final design revealed