This plastic electronic keyboard toy was manufactured in China. It creates distinct sounds corresponding the pressed keys. Simple construction made it easier to dissemble. The toy also has very few components and I have indicated each ones in the video above.
As I investigate each elements, I found that one of the most interesting part is the keyboards. Eight individual pieces are made of injection moulded plastic (?) and have build-in conductors underneath. When pressing these conductors, they touch the circuit board and complete the electrical circuit which create individual sounds. I believe that the designer has to truly understand the electric circuit operation to be able to come up with this solution to sound making.