The Latest code, Schematics, etc can be found here.
For a downloadable guide on how to assemble the Electronics Merit Badge Click Here.
The Assembled Kit
Assembling the Electronics Merit Badge Kit
Kit overview and Resistor Install
Inserting the LEDs
Soldering the LEDs
Inserting the Dual Inline (DIL) Socket
Inserting the Button and Potentiometer
Installing the 9 Volt Battery Clip
Assembling the Arduino