Here you have the slides and source code for the WebGL Codelab done at the Google Devfest-X BCN 2012 and also at SobrosoParty 2013
BCN DevFest-X Codelab description:
Bring your laptops to this codelab, in which we will introduce WebGL using the fantastic Three.js library by Ricardo Cabello. We will begin learning the basic usage of the library building scenes with geometric figures and lights. Then, we will export 3D models from Google Sketch Up to be shown in the web and finally you will be able to create a basic videogame controlling a 3D car. Ricardo Cabello will give us support with the Codelab and he will answer all your questions.