We use the Khan Academy computer programming course's core curriculum. Students learn the basics of programming in the JavaScript language, using the ProcessingJS library on top for drawing and animation. Students learn the basic concepts in the language, but in a visual way. For example, when we talk about nested for loops, we demonstrate how we can make a grid of gems on our screen.
The Khan Academy curriculum is viewable here: https://www.khanacademy.org/cs/programming.
Topics covered are: Basic statement syntax, Variables, Math operators and assignment operators, Strings, Functions, Logic and conditionals, Loops, Arrays, Objects, and Object-oriented JS.
The curriculum currently (September 2014) consists of 40 videos (talk-throughs), 31 challenges, and 9 projects. On average, the talk-throughs are 6 minutes long, the challenges take 5 minutes each to complete, and projects are often completed in 10-40 minutes, depending on how far the student wants to take them. There is thus around 15 hours of curriculum.