electronics through music - how to start

[Shevek60]

We unschool my 17 year old. He has never had an interest in science or making (other than bike repair) but his interest in music has led to an interest in effects pedals. He did a project at his homeschool center where he built a distortion pedal from a BYOC kit. Now he wants to learn to design effects pedals. Educated as a physicist, I am delighted that he wants to learn more about how the world works. Currently he knows nothing about waves or electronics, so I am wondering how to start, in a way to keep his interest but not overwhelm him (he is currently weak on math). I saw the Arduino hack on the distortion pedal (the Arduino runs a digital pot) and we may want to do that next. So one question is the Arduino Starter Kit from Arduino.cc looks good but it comes from Italy and Adafruit seems to be the only place in the US that has it in stock - is it really in stock? I like this kit because it has a Theremin project (my son is also doing an internship where he is making African instruments from trashpicked items.)
If not I was thinking of getting the Adafruit Arduino kit. Then I think, after we do this pedal hack prject, will he understand electronics any more than he does now?
I am also considering the lets do some other kit and learn some eletronics first approach. My electronics education ended with linear circuits, so I fell uncomfortable skipping that to breadboard ICs.
I am here trolling for suggestions. I learned electronics from my Dad's WWII Air Force manuals- that is no longer an option.

[BruceF]

In high school I spent much of my hard-earned cash on electronic components and Forrest M Mims III's Mini-Notebooks from Radio Shack. Those Mini-Notebooks were just the thing. They're gone now, but Adafruit sells the rightful heir to the Mini-Notebook throne. I may pick one up just for the nostalgia.

[Shevek60]

Thanks the only electronics book taht I know is Horowitz and Hill which is too intense for what my son has the attention for. He just gave me excited feedback on making a Theremin so that may decide things.