The LEGO Builder simulates the 3D LEGO bricks on screen, which is written in Processing, implemented with Simple OpenNI library that takes advantage of the power of Kinect. You can solely use your gestures to complete the interaction of picking a brick, moving, combining and rotating, etc. Instructions of existing models in Augmented Reality using the QR code is also provided. You could see and play with a dynamic 3D model of LEGO being displayed on a screen. This approach allows you to know how to build these model step by step and interact more deeply with LEGO in an easy and entertaining way.