The Crumble is an excellent board from Redfern Electronics that is idea for controlling LEDs and Motors and interfacing with real-world sensors. It comes with its own simple block programming interface.
Bumble (which is derived from Scratch) is an alternative system for programming the Crumble.
The advantage of using this, over the native interface, is that Scratch is the de-facto standard programming language in primary schools. This lets pupils (and teachers) apply their Scratch knowledge and skills to control and sense real-world devices such as traffic lights, burglar alarms and robots.
Click here to download and install Bumble.
Currently only for Windows