Under three weeks.. hmm.
haxe - http://www.haxe.org
lua - http://www.lua.org
processing - http://www.processing.org
smalltalk - http://www.smalltalk.org/main
puredata - http://puredata.info
arduino - http://arduino.cc/en
haxe - http://www.haxe.org
lua - http://www.lua.org
processing - http://www.processing.org
smalltalk - http://www.smalltalk.org/main
puredata - http://puredata.info
arduino - http://arduino.cc/en
three.js - http://mrdoob.github.com/three.js/
kinetic.js - http://kineticjs.com/
d3.js - http://d3js.org/
and then there is always the ubiquitous jquery for reducing the amount of browser stupidness - http://jquery.com/
And if you want to do apps, you could do worse than trying out unity3d - http://unity3d.com/ (It has a free version for learning it, though it will cost you a lot to do proper commercial work with it)