Is there a FIRST Robotics or FIRST tech challenge team at his school or in his area? (http://usfirst.org/) Programming robots is a great way to pull in kids (for FRC, they can use C/C++, LabVIEW or Java, FTC is LabVIEW or C I think).

I'd avoid HTML/CSS/PHP like the plague for a newbie. Have him write an ELIZA-style chatbot in Python or do some Project Euler questions in Python/C++/C#/Java